Agrochemical agents and their use

ABSTRACT

Azulmic acids, stabilized by condensation with carbonyl compounds, containing from 0.5 to 55 percent by weight of ionic groups of the formula ##STR1## in which R represents hydrogen, ammonium, one equivalent of a protonated or quaternized organic nitrogen base or of a sulphonium cation or one equivalent of a metal cation, 
     and containing from 0.5 to 15 percent by weight of groups formed by decarboxylation reaction of the formula ##STR2## and acid addition salts and complex compounds of these stabilized azulmic acids, and also mixed products of these stablized azulmic acids with additives can be used as agrochemicals. The products are particularly useful as fertilizers and as soil improving agents.

This is a division of application Ser. No. 11,541 filed Feb. 12, 1979now U.S. Pat. No. 4,251,255, Feb. 17, 1981.

The present invention relates to the use, as agrochemical agents, ofcertain azulmic acids stabilised by condensation with carbonylcompounds.

Polymeric hydrocyanic acids, so-called azulmic acids, and severalprocesses for their preparation have already been described (seeHouben-Weyl, volume 8 (1952), page 261; German Patent Specification Nos.662,338 and 949,060). Thus, polymeric hydrocyanic acid is obtained, forexample, by heating monomeric hydrocyanic acid to the reactiontemperature in dilute aqueous solution in the presence of a basiccatalyst, such as ammonia, sodium cyanide, sodium cyanate, potassiumcyanate or an alkaline earth, and, after the reaction has started,taking care that a reaction temperature of 120° C. is not exceeded bycooling the mixture (see German Patent Specification No. 662,338). In aparticular variant of this process, further hydrocyanic acid is added tothe mixture of solvent, hydrocyanic acid and catalyst in which thereaction has already started (see German Patent Specification No.949,060). These known hydrocyanic acid polymers are brown-black toblack, pulverulent products which are insoluble in all inert solvents,but which dissolve in 1 N aqueous sodium hydroxide solution, withdecomposition, even in the cold. A serious disadvantage of hydrocyanicacid polymers of this type is that when stored, whether under dryconditions or under moist conditions, small amounts of hydrogen cyanideare continuously split off even at room temperature. As the temperatureincreases, the rate at which hydrogen cyanide is split off alsoincreases. Amounts of hydrocyanic acid which are far above the legallyimposed maximum workplace concentration value of hydrocyanic acid of 11ppm therefore occur in containers holding azulmic acids no matter howmild the storage conditions are. Use in practice of the knownhydrocyanic acid polymers for the most diverse purposes thus presents anexceptional danger to the environment and is therefore scarcelypossible.

It is also known that hydrocyanic acid polymers can be used as nitrogenfertilisers (see H. Banthien "Synthetische Stickstoffdungemittel"("Synthetic Nitrogen Fertilisers") in "Handbuch der Pflanzenernahrungand Dungung" ("Handbook of Plant Nutrition and Fertilisation") II/2,1968, Springer-Verlag, Vienna/New York; German Patent Specification No.911,018; and Angew. Chem. 72, (1960) pages 379-384). A disadvantage is,however, that hydrocyanic acid is split off from these products,especially under hydrolytic conditions. Their use in practice asfertilisers is therefore scarcely possible.

According to a proposal by Th. Volker, the brown-black polymerichydrocyanic acid (azulmic acid) prepared in water has essentially thefollowing formula (see Angew. Chem. 72, (1960) pages 379-384): ##STR3##

A degree of polymerisation (HCN) of X=15-24 has been calculated from theoxygen contents of known azulmic acids, so that values of 1 to 4 resultfrom m in formula (I). The maximum molecular weights achieved for thepolymers are slightly above 700.

It has now been found that azulmic acids, stabilised by condensationwith carbonyl compounds, especially stabilized azulmic acids containingfrom 0.5 to 55 percent by weight of ionic groups of the general formula##STR4## in which R represents hydrogen, ammonium, one equivalent of aprotonated or quaternised organic nitrogen base or of a sulphoniumcation or one equivalent of a metal cation,

and containing from 0.5 to 15 percent by weight of groups formed bydecarboxylation reactions, of the formula ##STR5## and acid additionsalts and complex compounds of these stabilised azulmic acids, and alsomixed products of these stabilised azulmic acids with additives, can beused as agrochemical agents.

In particular, the present invention provides a fertiliser orsoil-improving composition comprising as active ingredient a stabilizedazulmic acid, an acid-addition salt thereof, a complex compound thereofor a mixed product thereof, in admixture with a solid or liquefiedgaseous diluent or carrier or in admixture with a liquid diluent orcarrier containing a surface-active agent.

The present invention also provides a method of fertilising or improvingsoil which comprises applying to soil a stabilized azulmic acid, anacid-addition salt thereof, a complex compound thereof or a mixedproduct thereof, alone or in admixture with a diluent or carrier.

It is to be described as exceptionally surprising that, in contrast tothe azulmic acids hitherto known, the azulmic acids which have beensubjected to a condensation reaction with carbonyl compounds, and acidaddition salts and complex compounds thereof and mixed products thereofwith additives are extremely resistant towards the splitting-off ofhydrogen cyanide. Thus, at temperatures of up to 130° C., in some casesat temperatures of up to 180° C. and in extreme cases even attemperatures of up to 200° C., virtually no hydrogen cyanide is splitoff from the products to be used according to the invention. The amountsof hydrogen cyanide split off which can be detected analytically arezero or, even under most unfavourable conditions, are below the legallyimposed, maximum workplace concentration values. Furthermore, theproducts to be used according to the invention are also very stabletowards the hydrolytic splitting-off of hydrogen cyanide. Thus, evenafter treating azulmic acids, stabilised as described above, in anaqueous medium at 100° C. for three hours, no cyanide ions, or less than0.2×10⁻⁶ g of cyanide ions per gram of water, can be detected.

It is also surprising that the azulmic acids stabilised by condensationwith carbonyl compounds, and acid addition salts and complex compoundsthereof and mixed products thereof with additives can be used asagrochemical agents. On the basis of the known state of the art, it hadto be assumed that, analogously to the case of the hydrocyanic polymersalready known, hydrogen cyanide would be split off from the productsaccording to the invention on storage and, above all, under hydrolyticconditions. However, in contrast to expectations, this is not the case.

The azulmic acids stabilised by condensation with carbonyl compounds,and acid addition salts and complex compounds thereof and mixed productsthereof with additives have a number of advantages. Thus, they have asubstantially higher swellability than previously known azulmic acids,and therefore, in contrast to the previously known azulmic acids, havethe most diverse uses. For example, not only are they stable towardssplitting off of hydrogen cyanide, but under hydrolytic conditions, suchas occur in soil, they can be degraded, with the assistance of soilbacteria, without hydrocyanic acid being liberated. They can thereforebe used as nitrogen fertilisers with a long-term action. Furthermore,substances to be used according to the invention that contain ions orsalts with appropriate ions can be used to supply plants with variousmacronutrients and/or micronutrients. Those substances which are chargedwith acids, for example nitric acid or phosphoric acid, or with ammoniumsalts are particularly valuable fertilisers, since they make bothorganically bonded nitrogen and inorganic nutrients available to plants.In addition, the substances to be used according to the invention aredistinguished by a high bonding capacity for harmful substancesoccurring in soil, for example undesired heavy metal ions. Moreover,they can be used as soil-improving agents and for other purposes inagriculture and horticulture. The invention thus represents a valuableenrichment of the art.

Preferred carbonyl compounds which the products to be used according tothe invention contain in a condensed form are aldehydes, ketones andketo esters with reactive carbonyl groups. Aldehydes which may bementioned in particular are formaldehyde, acetaldehyde,isobutyraldehyde, chloral, hydroxyethylaldehyde, hydroxypivalaldehyde,acrolein, crotonaldehyde, glyoxal, methylglyoxal, furfurol,hydroxymethylfurfurol, glucose, salicylaldehyde, hydroxyacetaldehyde,glyceraldehyde and other aldehydes which are formed from formaldehydeunder the conditions of the synthesis of formose. Formaldehyde isparticularly preferred. Ketones which may be mentioned in particular aredihydroxyacetone and cyclohexanone; ethyl acetoacetate may be mentionedas an example of a keto ester.

The structural defects which may be contained in a stabilised azulmicacids according to the invention are defined by the formulae (F₁) and(F₂). In the formula (F₁), R preferably represents hydrogen, ammonium orone equivalent of a cation of a metal from main groups I to V or fromsubgroups I to VIII of the Periodic Table, examples which may bementioned being the cations of lithium, sodium, potassium, beryllium,magnesium, calcium, strontium, barium, aluminium, thallium, tin,bismuth, copper, silver, gold, zinc, cadmium, titanium, zirconium,chromium, manganese, iron, cobalt, nickel, platinum and palladium. Rfurthermore preferably represents one equivalent of a protonatedalkylamine with 1 to 6 carbon atoms, a protonated dialkylamine with 1 to6 carbon atoms per alkyl group, a protonated trialkylamine with 1 to 6carbon atoms per alkyl group, a protonated hydroxyalkylamine with 1 to 6carbon atoms, a protonated di-(hydroxyalkyl)-amine with 1 to 6 carbonatoms per hydroxyalkyl group, a protonated tri-(hydroxyalkyl)-amine with1 to 6 carbon atoms per hydroxyalkyl group, a protonated cycloalkylaminewith 3 to 8 carbon atoms, a protonated alkylenediamine with 2 to 6carbon atoms, a protonated guanidine, melamine or dicyandiamide or of aprotonated, saturated or unsaturated heterocyclic nitrogen base with 5to 7 ring members and 1 to 3 nitrogen atoms in the heterocyclic ring,and also represents those cations which are formed by quaternisation,for example permethylation, of the abovementioned basic nitrogencompounds. Particularly preferred nitrogen bases in this context aremethylamine, dimethylamine, trimethylamine, ethylamine, diethylamine,triethylamine, tert.-butylamine, ethanolamine, diethanolamine,triethanolamine, cyclopropylamine, cyclopentylamine, cyclohexylamine,ethylenediamine, pyrrolidine, piperidine, morpholine, imidazole,pyrazole, 1,2,4-triazole, 1,2,3-triazole, 2-ethylimidazole andaminotriazole. R also preferably represents a trialkylsulphonium cation,in particular the triethylsulphonium cation.

By acid addition salts of azulmic acid which are stabilised bycondensation with carbonyl compounds there are to be understood thosesalts which are formed by addition of a proton of an inorganic ororganic acid onto an amino group or another suitable group in astabilised azulmic acid. Preferred inorganic acids here are hydrogenhalide acids, such as hydrofluoric acid, hydrochloric acid andhydrobromic acid; phosphorus acids, such as phosphoric acid, phosphorousacid, dialkylphosphoric acids, for example dibutylphosphoric acid,polyphosphoric acids with molecular weights from 6,000 to 40,000 andphospholine oxidephosphonic acids, for example those of the formulae##STR6## nitric acid; and acids derived from sulphur, such as sulphuricacid and sulphonic acids, examples which may be mentioned beingethylsulphonic acid, p-toluenesulphonic acid andnaphthalene-1,5-disulphonic acid. Preferred organic acids are saturatedor unsaturated carboxylic acids, such as acetic acid, propionic acid,2-ethylcaproic acid, acrylic acid, methacrylic acid, oleic acid andricinoleic acid; halogenocarboxylic acids, such as chloroacetic acid,dichloroacetic acid and trichloroacetic acid; dicarboxylic acids, suchas maleic acid, fumaric acid and succinic acid, and half-esters derivedtherefrom; and hydroxycarboxylic acids, such as hydroxyacetic acid,tartaric acid, citric acid and salicylic acid.

By azulmic acid complex compounds stabilised by condensation withcarbonyl compounds, there are to be understood, preferably, complexes ofstabilised azulmic acids and metal compounds or ammonium salts. Possiblemetal compounds here are, in particular, salts, acids, hydroxides andoxides of metals of main groups II to V or of sub-groups I to VIII ofthe Periodic Table. Examples which may be mentioned are calciumchloride, acetate, nitrate, hydroxide and oxide, strontium nitrate,barium chloride and acetate, borates, aluminium acetate and formate,thallium sulphate, thallium nitrate, silicon tetrachloride, sodium andpotassium silicate, tin(II) chloride, bismuth(III) hydroxide andBismuth(III) nitrate, copper sulphate, nitrate and acetate, silvernitrate, aurichlorohydric acid, zinc chloride and acetate, cadmiumchloride, titanium tetrachloride and tetrabutylate, zirconium sulphate,vanadates, chromium(III) chloride, molybdates, tungstates andhetero-polyacids thereof, manganese(II) sulphate and acetate, iron(II)sulphate and acetate and iron(III) chloride, cobalt chloride, nickelchloride, hexachloroplatinic acid and palladium(II) chloride. Possibleammonium salts are, in particular, ammonium nitrate and ammoniumacetate.

Additives which the products according to the invention can contain arenaturally occurring organic substances and products obtained therefrom,naturally occurring inorganic substances and products obtainedtherefrom, synthetic organic products, synthetic inorganic productsand/or mixed products consisting of organic and inorganic products.

Preferred naturally occuring organic substances and products obtainedtherefrom are, in this case, wood flour, lignin powder, lignin-sulphonicacids, ammonified lignin-sulphonic acids, humus, humic acids, ammonifiedhumic acids, peat, proteins and degradation products, for examplehydrolysis products, of yeasts, algal material (alginates),polypeptides, such as wool and gelatin, fishmeal and bone-meal, andfurthermore aminoacids, oligopolypeptides, pectins, monosaccharides,such as glucose and fructose, disaccharides, such as sucrose,oligosaccharides, polysaccharides, such as starch and cellulose, andalso hemicelluloses, homogenized materials of vegetable and animalorigin, active charcoals and ashes which are obtainable by partialoxidation, complete oxidation or combustion of organic substances formedby photosynthesis or of customary fuels, fir ash, broom ash, ash ofSerbian spruce, oak ash, birch ash, beech ash, willow ash and tobaccoleaf ash being mentioned in particular.

Preferred naturally occurring inorganic substances and products obtainedtherefrom are silicates, such as aluminium silicates, calcium silicates,magnesium silicates and alkali metal silicates, furthermore sea sand andother naturally occurring silicon dioxides, silicic acids, in particulardisperse silicic acids, silica gels, and also clay minerals, mica,carbonates, such as calcium carbonate, phosphorite and phosphates, suchas calcium phosphate and ammonium magnesium phosphate, sulphates, suchas calcium sulphate and barium sulphate, and in addition oxides, such aszirconium dioxide, nickel oxide, palladium oxide, barium oxide, disperseantimony oxides and aluminium oxides, such as bauxite, and further, flyashes and the most diverse types of carbon black.

Preferred synthetic organic products are aminoplast condensates, inparticular those of urea, dicyandiamide, melamine or oxamide andaldehydes, such as formaldehyde, acetaldehyde, isobutyraldehyde,hydroxypivaldehyde, crotonaldehyde, hydroxyacetaldehyde, furfurol,hydroxymethylfurfurol, glyoxal and glucose, particular products whichmay be mentioned being condensation products of urea and formaldehyde,urea and glyoxal, urea and acetaldehyde, urea and isobutyraldehyde, ureaand crotonaldehyde, urea and hydroxypivalaldehyde and2-oxo-4-methyl-6-ureido-hexahydropyrimidine, which is a knowncondensation product of 1 mol of crotonaldehyde and 2 moles of urea andis formed from the intermediate product crotonylidene-diurea bysaturation of the double bond and has the formula ##STR7## Furtherpreferred synthetic organic products are plastics, such as polyamidepowders, polyurethane powders and polycarbodiimides, and furthermorepolymeric quinones, addition products and condensation products ofquinones, in particular benzoquinone, with amines or ammonia, and alsowith aldehydes, in particular formaldehyde, crosslinked gelatin,synthetic agents for improving soil, such as, for example, the productknown as Hygromull (=urea/formaldehyde resin flakes), furthermoresynthetic sugars, for example, formose sugar mixtures prepared fromformaldehyde, and also sparingly soluble cane sugar complexes, such asthe sucrose-calcium oxide complex having the composition 1 mol ofsucrose to 3 mols of calcium oxide, and finally organic ammonium salts,such as ammonium carbaminate, and other organic nitrogen compounds, suchas hexamethylenetetramine and hexahydrotriazines.

Preferred synthetic inorganic products which may be mentioned arefertilisers, such as superphosphate, basic slag, Rhenania phosphate,phosphorite, calcium cyanamide, calcium ammonium nitrate, Leunasaltpeter, potassium phosphates, potassium nitrate and ammonium nitrate;pigments, such as iron oxides and titanium dioxides; metal oxides andmetal hydroxides, such as calcium oxide, calcium hydroxide, bismuthhydroxide, manganese hydroxide and magnesium hydroxide, hydroxides whichare prepared in situ being particularly preferred; synthetic silicicacids, in particular silicic acid prepared in situ, and salts thereof,and also waterglass; and salts such as cobalt molybdate, ammoniumcarbonate and calcium carbonate.

Preferred mixed products consisting of inorganic and organic productsare neutral, basic or acid soils, naturally occurring agents forimproving soil, biologically active garden mould and sewage sludges.

The additives can be physically and/or chemically bonded to thestabilised azulmic acid in an amount of from 1 to 95 percent by weight,preferably from 5 to 90 percent by weight. In some cases, the stabilisedazulmic acids are coated by the additives. Stabilised azulmic acidscoated, for example micro-encapsulated, by polycarbodiimides may bementioned as an example of products of this type.

The azulmic acids, stabilised by condensation with carbonyl compounds,which can be used according to the invention, acid addition salts andcomplex compounds thereof and mixed products thereof with additives havenot hitherto been disclosed. However, they can be prepared in a simplemanner by several processes. Thus, the azulmic acids, stabilised bycondensation with carbonyl compounds, which can be used according to theinvention, acid addition salts and complex compounds thereof and mixedproducts thereof with additives may be obtained by processes in which

(1) modified azulmic acids optionally containing additives andcontaining from 0.5 to 55 percent by weight of ionic groups of thegeneral formula ##STR8## in which R has the meaning stated above,

and containing from 0.5 to 15 percent by weight of groups of the formula##STR9## are subjected to a condensation reaction with carbonylcompounds in an aqueous medium, optionally in the presence of additives,or in which

(2) acid addition salts or complex compounds, optionally containingadditives, of modified azulmic acids containing from 0.5 to 55 percentby weight of ionic groups of the general formula ##STR10## in which Rhas the meaning stated above,

and containing from 0.5 to 15 percent by weight of groups of the formula##STR11## are subjected to a condensation reaction with carbonylcompounds in an aqueous medium, optionally in the presence of additives,or in which

(3) azulmic acids which are almost free from structural defects aresubjected to a condensation reaction with carbonyl compounds in anaqueous medium, optionally in the presence of additives, or in which

(4) hydrocyanic acid is polymerised under hydrolysing conditions in anaqueous medium with the aid of basic catalysts, optionally in thepresence of additives, and the reaction products are then subjected to acondensation reaction with carbonyl compounds, without prior isolation,in an aqueous medium, optionally in the presence of additives, or inwhich

(5) modified azulmic acids containing from 0.5 to 55 percent by weightof ionic groups of the general formula ##STR12## in which R has themeaning stated above

and containing from 0.5 to 15 percent by weight of groups of the formula##STR13## are reacted with bases in an aqueous medium, the cation isoptionally replaced by treatment with metal salts and the products arethen subjected to a condensation reaction with carbonyl compounds in anaqueous medium, optionally in the presence of additives, in an aqueousmedium, or in which

(6) modified azulmic acids are treated with organic or inorganic acidsin an aqueous medium and the products are then subjected to acondensation reaction with carbonyl compounds in an aqueous medium,optionally in the presence of additives, or in which

(7) azulmic acids which are almost free from structural defects aresubjected to a condensation reaction with carbonyl compounds in anaqueous medium, in the presence of hydrolytically degradable naturallyoccurring substances and in the presence of an acid, and the productsprepared by the processes mentioned are then optionally treated with anacid or base.

In the present case, by modified azulmic acids which are used asstarting materials in some of the processes indicated above, there areto be understood those hydrocyanic acid polymers which contain ionic andnon-ionic groups of the formulae ##STR14## Groups of this type originatefrom nitrile groups, which are present in azulmic acid and can beregarded as terminal points for the cyclising nitrile polymerisation.

In the ideal case, the transition of a nitrile group of azulmic acidinto a corresponding carboxyl group can be illustrated, by means offormulae, as follows: ##STR15##

It is, of course, also possible to form amide, imide, amidine or lactamgroups from nitrile groups. Thus, for example the formation of amidegroups can be represented by the equation which follows. ##STR16##

Ionic or non-ionic groups of the above formulae are produced not only atthe nitrile groups which are already present in the polymer employed,but also at those nitrile groups which are formed by catalyticdecyclisation reactions. Furthermore, various other hydrolysis reactionsare responsible for the formation of structural defects. For example, a##STR17## group, which is to be regarded as an α-aminonitrile in theazulmic acid molecular structure, can be converted into a carbonyl groupby splitting off hydrogen cyanide and a subsequent topochemicalhydrolysis reaction according to the equation which follows: ##STR18##

In the following text, the ionic groups of the general formula ##STR19##are designated F₁ structural defects and the groups of the formula##STR20## are designated F₂ structural defects.

The F₂ structural defects are formed from the F₁ structural defects, inwhich R represents hydrogen or another suitable ion, according to theequation which follows: ##STR21## or, in the azulmic acid molecularunit, the modification of the structural defects by a decarboxylationreaction ##STR22## results in an increase in the concentration of NH₂groups, a loss in acidity, and an increase in basicity.

As can be seen from the formula (II) indicated above, each F₁ structuraldefect produced is directly adjacent to an amino group in the α-positionand to an amino group in the β-position. Thus, at F₁ structural defectsof the formula ##STR23## either intramolecular zwitterionic salts of theformula ##STR24## are formed, or intermolecularly crosslinked salts,represented ideally as follows: ##STR25## are formed between severalazulmic acid molecules. The formation of intramolecular salts, that isto say 5-membered rings, is preferred.

Since the formation of the F₁ structural defects is coupled with theliberation of ammonia and the formation of the F₂ structural defects iscoupled with the liberation of carbon dioxide, the amount of ammonia andcarbon dioxide evolved is a quantitative measure of the number ofstructural defects produced. The quotient of the molar amount of ammoniaevolved and the molar amount of carbon dioxide evolved providesinformation on the ratio of F₁ structural defects to F₂ structuraldefects.

In the following text, the content of structural defects, in percent byweight, in the modified azulmic acids is in each case determined byrelating the equivalent weight of the structural defect concerned(=ionic or non-ionic grouping F₁ or F₂) to the corresponding weight (100g) not converted into an ionic or non-ionic grouping. Thus, for example,the concentration of structural defects for an F₁ structural defect inwhich R represents hydrogen is calculated from the particular molaramount of ammonia formed and the fact that the associated ionic groupingof the formula ##STR26## has an equivalent weight of 73.

In an analogous manner, the content of F₂ structural defects iscalculated from the particular molar amount of carbon dioxide evolvedand the fact that the relevant grouping of the formula ##STR27## has anequivalent weight of 29.

The common characteristic of processes (1) to (7) for the preparation ofthe substances which can be used according to the invention is thecondensation of amino, amide, amidine or lactam groups, present in theazulmic acids employed, with carbonyl groups. If, for example,formaldehyde is used as the carbonyl component, condensation thereofwith an amino group of an azulmic acid can be illustrated, for example,by the equation which follows: ##STR28##

Reactions which lead to methylol compounds, N,N-methylene compounds orcompounds with methylene ether linkages (>N--CH₂ --O--CH₂ --N<) canproceed in addition to the formation of azomethine groups shown by wayof the equation. Azomethine groups (--N═CH₂) readily crosslink to givehexahydrotriazine structures, partial formation of hexahydropyrimidinederivatives by intramolecular condensation of cis-amino groups presentin the α-position also being possible.

In process (1), modified azulmic acids optionally containing additivesand containing from 0.5 to 55 percent by weight of ionic groups of theformula ##STR29## and containing from 0.5 to 15 percent by weight ofgroups of the formula ##STR30## are subjected to a condensation reactionwith carbonyl compounds in an aqueous medium, optionally in the presenceof additives.

In the formula (F₁), R preferably represents those substituents whichhave already been mentioned as preferred for R in connection with thedescription of the substances to be used according to the invention.

The modified azulmic acids to be used as starting materials in process(1) (=azulmic acids containing structural defects) can contain 1 to 95percent by weight, preferably 5 to 90 percent by weight, of additives.Possible additives here are naturally occurring organic substances andproducts obtained therefrom, naturally occurring inorganic substancesand products obtained therefrom, synthetic organic products, syntheticinorganic products and/or mixed products consisting of organic andinorganic products. These include, preferably, those materials whichhave already been mentioned as preferred in connection with thedescription of the additives optionally present in the substances to beused according to the invention.

The modified azulmic acids optionally containing additives, used asstarting materials in process (1) are hitherto unknown. However, theycan be prepared in a simple manner by various processes. Thus, theproducts concerned, which are the subject of a separate PatentApplication, are obtained by a process in which

(A) azulmic acid, which is known and almost free from structuraldefects, in an aqueous medium,

(a) is treated with organic or inorganic acids, optionally in thepresence of additives, or

(b) is treated with bases or basic salts, optionally in the presence ofadditives, or

(c) is treated with water in the neutral range, or

(d) is treated with vegetable ashes, catalytically active naturallyoccurring substances and/or fertilisers, or

(e) is treated with metal salts, optionally in the presence of oxidisingagents and optionally in the presence of organic acids, or

(f) is treated with metal salt complexes of stabilised azulmic acids, or

(g) is treated with oxidising agents, or in which

(B) hydrocyanic acid is polymerised under hydrolysing conditions in anaqueous medium with the aid of basic catalysts, optionally in thepresence of additives, and the products prepared by the processesmentioned are then optionally treated with an acid or base.

Hydrocyanic acid polymers which are almost free from structural defects,so-called azulmic acids, may be used as starting materials in thepreparation of the modified azulmic acids, optionally containingadditives, by process (A), variants (a) to (g). Azulmic acids of thistype which are almost free from structural defects are already known(see Houben-Weyl, volume 8 (1952), page 261; German Patent Specification662.338; and DT-OS (German Published Specification) No. 949,060).

According to variant (a) of process (A), the azulmic acids which arealmost free from structural defects are treated with inorganic ororganic acids, optionally in the presence of additives. Preferredinorganic or organic acids for this treatment are all those which havealready been listed as preferred in the description of the stabilisedacid-addition products of azulmic acid. Additives which can be used arenaturally occurring organic substances and products obtained therefrom,naturally occurring inorganic substances and products obtainedtherefrom, synthetic organic products, synthetic inorganic productsand/or mixed products consisting of organic and inorganic products.These include, preferably, all those materials which have already beenmentioned as preferred in connection with the description of theadditives optionally present in the substances to be used according tothe invention.

Variant (a) of process (A) is carried out in an aqueous medium,preferably in water. However, it is also possible to replace some of thewater by other diluents, such as hydrogen sulphide or alcohols, methanoland ethanol being mentioned in particular.

In the case of variant (a) of process (A), the reaction temperatures canbe varied within a substantial range. In general, the reaction iscarried out between 0° C. and 200° C., preferably between 20° C. and120° C.

In general, the reaction according to variant (a) of process (A) iscarried out under normal pressure. However, it is also possible to carryout the reaction under increased pressure.

In carrying out variant (a) of process (A), a catalytic amount or 1 to 4moles of an inorganic or organic acid and optionally an amount ofadditives such that the proportion thereof in the end product is between1 and 95 percent by weight, preferably between 5 and 90 percent byweight, are employed per mole (relative to the molecular unit ##STR31##with the equivalent weight 54) of azulmic acid which is almost free fromstructural defects. The mixture is worked up by customary methods. Ingeneral, a procedure is followed in which, after the reaction has ended,the reaction mixture is filtered and the solid product obtained isappropriately washed and dried.

If nitric acid is used for producing structural defects in carrying outvariant (a) of process (A), and the reaction temperature is thereby keptrelatively low, preferably between 20° and 30°, traces of hydrocyanicacid split off are oxidised, whilst at the same time addition reactionsof nitric acid with the amino groups of the modified azulmic acids takeplace extremely readily, and types of modified azulmic acids whichcontain ionic groups of the formula ##STR32## on their amino groups areobtained by a simple topochemical reaction.

In this manner, about 0.5 mol of nitric acid is bonded per 100 parts byweight of modified azulmic acid. Depending on the type of process andthe reaction time of the dilute nitric acid on the modified azulmicacids, about 30 to 50% of the amino groups present are available forsalt formation. Traces of free nitric acid can advantageously beconverted into ammonium nitriate by gassing the products with gaseousammonia, the reaction advantageously being carried out in the solidphase in a fluidised bed.

If phosphoric acid or phosphorous acid is used for producing structuraldefects in carrying out variant (a) of process (A), and the reactiontemperatures are kept relatively low, preferably between 20° C. and 55°C., decarboxylation reactions and the production, associated therewith,of F₂ structural defects are largely suppressed. At the same time, theacids are bonded extremely readily by the amino groups of the modifiedazulmic acids in a heterogeneous reaction. In this manner, about 0.2 molof phosphoric acid, or about 0.5 mol of phosphorous acid, are bonded byabout 100 parts by weight of modified azulmic acid within five minutes.The salts formed are almost water-insoluble. Small amounts of freephosphoric acid or phosphorous acid contained in the products canadvantageously be converted into the corresponding ammonium salts bytreating the products with gaseous ammonia, the reaction advantageouslybeing carried out in the solid phase in a fluidised bed.

In a particular embodiment of variant (a) of process (A), the azulmicacid is reacted with 0.2 to 80% strength phosphoric acid or phosphorousacid in the presence of naturally occurring hydrolytically degradablesubstances, for example celluloses, hemicelluloses, sugars, lignin,polymeric quinones, wood flour, vegetable material, polypeptides, suchas gelatin and wool, and furthermore yeast proteins, algal compositionsand peat compositions. In this embodiment, the structural defects areproduced with simultaneous hydrolytic degradation of the particularnaturally occurring substances employed. If polypeptides are used, theseare split into amino-acid mixtures. Because of its numerous aminogroups, the azulmic acid bonds about 0.3 to 0.4 mol of phosphoric acidor phosphorous acid, whilst the phosphoric acid salts of the aminoacidsor those of the oligopolypeptides, or the other low-moleculardegradation products of the naturally occurring substances employed arefrequently fixed by the azulmic acid matrix in a large amount, even whenthey are water-soluble. Excess acid, for example phosphoric acid, can beprecipitated as calcium phosphate on the azulmic acid matrix by addingcalcium hydroxide. If hydrolysed sugars and oligosaccharides are presentin this case, they are absorbed on the azulmic acid in the form of theircalcium complexes, which are usually sparingly soluble. The processproducts obtained by this variant of process (A) can be stored for arelatively long period without unpleasant odours being formed, as isotherwise the case when naturally occurring substances such asoligopeptides, peptide/sugar mixtures and the like are degraded bybiological processes.

A further particular embodiment of variant (a) of process (A) consistsof a procedure in which, in order to produce the structural defects, 1to 4 mols of 1 molar phosphoric acid solution are employed and theexcess phosphoric acid is then precipitated as calcium phosphate byadding calcium chloride, as magnesium phosphate by adding magnesiumchloride or as ammonium magnesium phosphate by adding ammonium andmagnesium salts. Additives of the most diverse nature can also be usedat the same time during this procedure. Particularly preferred additivesin this case are vegetable ashes, insolube polyquinones, additionproducts or condensation products of benzoquinone and amines, inparticular ammonia, and furthermore lignin-sulphonic acids, humic acids,diverse fly ashes, bauxite, aluminium oxide, cobalt molybdate, silicondioxide, active charcoal, zirconium dioxide, nickel oxide, palladiumoxide and barium oxide. Further preferred possible additives are sugars,such as cane sugar and other sugars containing no free aldehyde groups,or formose sugar mixtures prepared from formaldehyde. These very diversetypes of sugars can be fixed in the channels and pores of the solidazulmic acid matrices. Furthermore, the various sugars can also beabsorbed onto the azulmic acids in the form of their calcium complexes,which in most cases are sparingly soluble.

According to variant (b) of process (A), the azulmic acids which arealmost free from structural defects are treated with bases or basicsalts, optionally in the presence of additives. Both organic andinorganic bases can be used as the bases here. Organic bases which canpreferably be used are ammonia, alkylamines with 1 to 6 carbon atoms,dialkylamines with 1 to 6 carbon atoms per alkyl group, trialkylamineswith 1 to 6 carbon atoms per alkyl group, hydroxyalkylamines with 1 to 6carbon atoms, di-(hydroxyalkyl)-amines with 1 to 6 carbon atoms perhydroxyalkyl group, tri-(hydroxyalkyl)-amines with 1 to 6 carbon atomsper hydroxyalkyl group and alkyl-hydroxyalkylamines with 1 to 6 carbonatoms in the alkyl group and in the hydroxyalkyl group, andcycloalkylamines with 3 to 8 carbon atoms, alkylenediamines with 2 to 6carbon atoms, guanidine, melamine, dicyandiamide, saturated orunsaturated heterocyclic nitrogen bases with 5 to 7 ring members and 1to 3 nitrogen atoms in the heterocyclic ring, and those bases which arederived from the compounds formed by quaternisation, for examplepermethylation, of the abovementioned nitrogen compounds, andfurthermore those bases which are derived from trialkylsulphoniumcompounds. Particularly preferred nitrogen bases in this context areammonia, methylamine, methylethanolamine, dimethylamine, trimethylamine,ethylamine, diethylamine, triethylamine, tert.-butylamine, ethanolamine,diethanolamine, triethanolamine, cyclopropylamine, cyclopentylamine,cyclohexylamine, ethylenediamine, pyrrolidine, piperidine, morpholine,imidazole, pyrazole, 1,2,4-triazole, 1,2,3-triazole, 2-ethyl-imidazole,aminotriazole and triethylsulphonium hydroxide.

Inorganic bases which can preferably be used are alkali metal hydroxidesand alkaline earth metal hydroxides. Lithium hydroxide, sodiumhydroxide, potassium hydroxide, magnesium hydroxide, calcium hydroxide,strontium hydroxide and barium hydroxide may be mentioned in particular.

Preferred possible basic salts for carrying out variant (b) of process(A) are alkali metal sulphides, such as sodium sulphide, sodiumbisulphide and potassium bisulphide, and further sodium thiosulphate,ammonium thiosulphate, ammonium polysulphides, calcium bisulphide,calcium thiosulphate and calcium cyanamide, and also potassiumcarbonate, potassium bicarbonate, potassium cyanate and waterglass(sodium waterglass or potassium waterglass). Mixtures of ammonia andsodium thiosulphate, ammonium thiosulphate, sodium bisulphide, sodiumsulphide and/or ammonium polysulphides are also particularly suitablefor producing structural defects by this method.

Additives which can be used in carrying out variant (b) of process (A)are naturally occurring organic substances and products obtainedtherefrom, naturally occurring inorganic substances and productsobtained therefrom, synthetic organic products, synthetic inorganicproducts and/or mixed products consisting of organic and inorganicproducts. These additives include, preferably, all those materials whichhave already been mentioned as preferred in connection with thedescription of the additives optionally present in the substances to beused according to the invention.

Variant (b) of process (A) is carried out in an aqueous medium or in anaqueous-alcoholic medium. A preferred reaction medium is water, or amixture of water and an alcohol, such as methanol or ethanol. However,it is also possible to replace some of the water by hydrogen sulphide.If the reaction is carried out in the presence of hydrogen sulphide orin the presence of reagents which release hydrogen sulphide under thereaction conditions and the reaction temperature is kept between 70° C.and 100° C., small amounts of hydrocyanic acid split off are convertedinto carbon oxysulphide and ammonia, structural defects simultaneouslybeing produced.

The reaction temperatures can be varied within a substantial range inthe case of variant (b) of process (A). In general, the reaction iscarried out at temperatures between 0° C. and 200° C., preferablybetween 20° C. and 150° C.

In general, the reaction according to variant (b) of process (A) iscarried out under normal pressure. However, it is also possible to carryout the reaction under increased pressure. The latter is particularlyadvisable if gaseous ammonia is used for producing structural defects.

In carrying out variant (b) of process (A), a catalytic amount, or 1 to4 moles, preferably 1 to 2 moles, of base or basic salt and optionallyan amount of additives such that their proportion in the end product isbetween 1 and 95 percent by weight, preferably between 5 and 90 percentby weight, are employed per mole (relative to the molecular unit##STR33## with the equivalent weight 54) of azulmic acid which is almostfree from structural defects. The mixture is worked up by customarymethods. In general, a procedure is followed in which, after thereaction has ended, the reaction mixture is filtered and the solidproduct obtained is appropriately washed and dried. The base stillcontained in the end product can also advantageously be neutralised byadding a corresponding amount of acid, such as, for example, phosphoricacid, so that the products formed then also contain the particularsalts.

If an excess of acid is used in this neutralisation, acid addition saltsof the particular modified azulmic acids are formed.

If strong bases are used for producing structural defects in carryingout variant (b) of process (A), azulmic acids with particularly highcontents of structural defects can be prepared after relatively longreaction times. The products formed have a polyelectrolyte character. Inthe case where potassium hydroxide is employed as the base, the idealcourse of a reaction of this type can be illustrated by the equationwhich follows. ##STR34##

If an excess of concentrated (25% strength) ammonia solution is used inthis variant (b) of process (A), and the reaction is carried out at roomtemperature, after a reaction time of about 6 to 20 hours, modifiedazulmic acids which contain a high proportion of structural defects andin which some of the carboxyl groups are present in the form of ammoniumcarboxylate groups are obtained. However, it is also possible to convertmodified azulmic acids in which free carboxyl groups are present intothe corresponding products containing the ammonium salt by gassing withammonia in a fluidised bed.

In a particular embodiment of variant (b) of process (A), the azulmicacid is reacted with gaseous ammonia under pressure in anaqueous-alcoholic medium at temperatures between 120° C. and 140° C.Modified azulmic acids which have a high content of ammonium carboxylategroups are formed in this procedure. The free amino groups contained inthese products are capable of additionally bonding acids, for examplephosphoric acid, so that the end products contain ammonium ions and acidradicals side by side.

In a further particular embodiment of variant (b) of process (A), theazulmic acid is reacted with catalytic amounts, or even with largeramounts, of waterglass--about 1 to 4 mols of waterglass per 100 g ofazulmic acid--in a topochemical reaction. In this procedure, modifiedazulmic acids charged with potassium ions or sodium ions are formed, thesaponifiable nitrile groups of which act as latent acids and precipitatesilicic acids. The latter are absorbed, in fine distribution, onto thereaction products. Any excess sodium silicate or potassium silicatepresent can be precipitated by simple gassing of the particulardispersions with carbon dioxide, or can be precipitated in aparticularly advantageous manner by adding phosphoric acid or calciumchloride mixed with potassium phosphates or sodium phosphates or calciumsilicates.

According to variant (c) of process (A), the azulmic acids which arealmost free from structural defects are treated with distilled water inthe neutral range, preferably at pH values between 6 and 6.5, for 4 to60 hours. The reaction temperatures can be varied within a substantialrange in this procedure. In general, the reaction is carried out attemperatures between 60° C. and 150° C., preferably between 80° C. and120° C. In general, the reaction is carried out under normal pressure.However, it is also possible to carry it out under increased pressure.Isolation of the reaction products is also carried out by customarymethods in this variant of process (A). In general, a procedure isfollowed in which, after the reaction has ended, the reaction mixture isfiltered and the solid product obtained is dried.

According to variant (d) of process (A), the azulmic acids which arealmost free from structural defects are treated with vegetable ashes,catalytically active naturally occurring substances and/or fertilisers.

Possible vegetable ashes in this procedure are the combustion productsof the most diverse substances formed by photosynthesis. Preferred asheswhich may be mentioned are the ashes of fir, broom, Serbian spruce, oak,birch, beech, willow, tobacco leaves and tobacco stalks, and furthermoreof cereals, such as rye or barley, and also of fungi, for example ediblemushrooms, and of apples, carrots, potato tubers and leaves of whitecabbage. It is particularly advantageous to use potassium-rich varietiesof ash. By ashes there are also to be understood here mixtures ofvarious vegetable ashes.

Preferred catalytically active naturally occurring substances arebiologically active garden mould and basic or acid soils of the mostdiverse nature.

All the commercially available fertilisers can be used as fertilisers inthe production of structural defects according to variant (d) of process(A). Preferred fertilisers which may be mentioned are varieties of peatcharged with plant nutrients, superphosphate, basic slag, Rhenaniaphosphate, phosphorite, calcium cyanamide, calcium ammonium nitrate,Leuna saltpeter, potassium phosphates, potassium nitriate and ammoniumnitrate.

Variant (d) of process (A) is carried out in an aqueous medium,preferably in water. However, it is also possible to replace some of thewater by other diluents, such as hydrogen sulphide or alcohols, methanoland ethanol being mentioned in particular.

The reaction temperatures can be varied within a substantial range inthe case of variant (d) of process (A). In general, the reaction iscarried out between 50° C. and 150° C., preferably between 80° C. and120° C.

In general, the reactions according to variant (d) or process (A) arecarried out under normal pressure. However, it is also possible to carryout the reactions under increased pressure.

In carrying out variant (d) of process (A), the azulmic acid is reactedwith catalytic or even with larger amounts of vegetable ashes,catalytically active naturally occurring substances and/or fertilisers.If the vegetable ashes, catalytically active naturally occurringsubstances and/or fertilisers are used in a relatively large amount,these substances are not only used for producing structural defects, butthey are also simultaneously contained, as additives, in the productsformed. The mixture is worked up by customary methods. In general, aprocedure is followed in which, after the reaction has ended, thereaction mixture is filtered and the solid product obtained isappropriately washed and dried.

According to variant (e) of process (A), the azulmic acids which arealmost free from structural defects are treated with metal compounds,optionally in the presence of oxidising agents and optionally in thepresence of organic acids.

Preferred metal compounds here are salts of metals of main groups II toV or of sub-groups I to VIII of the Periodic Table. Examples which maybe mentioned are calcium chloride, acetate and nitrate, strontiumnitrate, barium chloride and acetate, aluminium acetate and formate,thallium sulphate and nitrate, silicon tetrachloride, sodium silicateand potassium silicate, tin(II) chloride, bismut(III) nitrate, coppersulphate, nitrate and acetate, silver nitrate, aurichlorohydric acid,zinc chloride and acetate, cadmium chloride, titanium tetrachloride andtetrabutylate, zirconium sulphate, chromium(III) chloride, manganese(II)sulphate and acetate, iron(II) sulphate and acetate and iron(III)chloride, cobalt chloride, nickel chloride, hexachloroplatinic acid andpalladium(II) chloride. Further metal compounds which can preferably beused are the acids of vanadium, molybedenum and tungsten, andheteropolyacids thereof.

Possible oxidising agents which can be present in carrying out variant(e) of process (A) are all the customary agents which release oxygen.Air and nitric acid can preferably be used.

Preferred organic acids which can be present in carrying out variant (e)of process (A) are saturated and unsaturated, optionally substitutedcarboxylic acids. Formic acid, acetic acid, propionic acid,2-ethyl-caproic acid, acrylic acid, methacrylic acid, oleic acid,ricinoleic acid, chloroacetic acid, dichloroacetic acid, trichloroaceticacid and hydroxyacetic acid may be mentioned in particular.

In general, variant (e) of process (A) is carried out in an aqueousmedium, preferably in water. However, it is also possible to replacesome of the water by other diluents, such as acids or organichydrocarbons, formic acid and xylene being mentioned in particular.

The reaction temperatures can be varied within a substantial range inthe case of variant (e) of process (A). In general, the reaction iscarried out between 0° C. and 150° C., preferably between 20° C. and120° C.

In general, the reaction according to variant (e) of process (A) iscarried out under normal pressure. However, it is also possible to carryout the reaction under increased pressure.

In carrying out variant (e) of process (A), a catalytic amount, or evena larger amount--about 1 to 2 mols--of metal compound and optionally acatalytic amount, or even a larger amount, of oxidising agent andoptionally a catalytic amount, or even a larger amount, of organic acidare employed per mole (relative to the molecular unit ##STR35## with theequivalent weight 54) of azulmic acid. The mixture is worked up bycustomary methods. In general, a procedure is followed in which, afterthe reaction has ended, the reaction mixture is filtered and the solidproduct thereby obtained is appropriately washed and dried.

Any excess metal compounds present in the products obtained can beprecipitated in the form of finely divided precipitates, which arefrequently sparingly soluble, by adding bases, such as ammonia, sodiumhydroxide or potassium hydroxide, or by adding acids, such as phosphoricacid, depending on the metal compound.

According to variant (f) of process (A), the azulmic acids which arealmost free from structural defects are treated with metal saltcomplexes of azulmic acids stabilised with carbonyl compounds.

The preparation of the metal salt complexes, required as startingmaterials, of azulmic acids stabilised with carbonyl compounds isdescribed in connection with the preparation of the substances to beused according to the invention.

Metal salt complexes which can preferably be used in this procedure arethose which are derived from those metal compounds which have alreadybeen mentioned as preferred in connection with variant (e) of process(A).

Variant (f) of process (A) is carried out in an aqueous medium,preferably in water. However, it is also possible to replace some of thewater by other diluents, such as alcohols.

The reaction temperatures can be varied within a substantial range inthe case of variant (f) of process (A). In general, the reaction iscarried out between 0° C. and 150° C., preferably between 20° C. and120° C.

In general, the reaction according to variant (f) of process (A) iscarried out under normal pressure. However, it is also possible to carryout the reaction under increased pressure.

In carrying out variant (f) of process (A), 0.5 to 1 mole of metal saltcomplex of stabilised azulmic acid is preferably employed per mole(relative to the molecular unit ##STR36## with the equivalent weight 54)of azulmic acid which is almost free from structural defects. Themixture is worked up by customary methods. In general, a procedure isfollowed in which, after the reaction has ended, the reaction mixture isfiltered and the solid product thus obtained is appropriately washed anddried.

Any excess metal compounds present in the products which can be preparedaccording to variant (f) of process (A) can be precipitated in the formof finely divided precipitates, which are frequently sparingly soluble,by adding bases, such as ammonia, sodium hydroxide or potassiumhydroxide, or by adding acids, such as phosphoric acid, depending on themetal compound.

According to variant (g) of process (A), the azulmic acids which arealmost free from structural defects are treated with oxidising agents.Possible oxidising agents here are all the customary reagents having anoxidising action. Air, oxygen, potassium permanganate, hydrogenperoxide, chromic acid and bleaching powder can preferably be used.

Variant (g) of process (A) is carried out in an aqueous medium,preferably in water. However, it is also possible to replace some of thewater by other diluents, such as organic carboxylic acids, formic acidand acetic acid being mentioned in particular.

The reaction temperatures can be varied within a substantial range inthe case of variant (g) of process (A). In general, the reaction iscarried out between 0° C. and 150° C., preferably between 20° C. and120° C.

In general, the reaction according to variant (g) of process (A) iscarried out under normal pressure. However, it is also possible to carryout the reaction under increased pressure.

In carrying out variant (g) of process (A), a catalytic amount, or evena larger, optionally equimolar, amount, of oxidising agent is employedper mole (relative to the molecular unit ##STR37## with the equivalentweight 54) of azulmic acid which is almost free from structural defects.The mixture is worked up by customary methods. In general, a procedureis followed in which, after the reaction has ended, the reaction mixtureis filtered and the solid product obtained is appropriately washed anddried.

According to process (B), monomeric aqueous hydrocyanic acid ispolymerised under hydrolysing conditions with the aid of basiccatalysts, optionally in the presence of additives. Dilute aqueoushydrocyanic acid solutions are used as starting materials in thisprocedure. In general, solutions with a hydrocyanic acid concentrationof between 10 and 30%, preferably between 15 and 25%, are used.

Possible basic catalysts for process (B) are organic and inorganic basesand basic salts of the most diverse nature. Alkali metal cyanides andalkali metal cyanates, such as sodium cyanide, potassium cyanide, sodiumcyanate and potassium cyanate, and furthermore amines and ammonia, canpreferably be used. Mixtures of the most diverse bases or basic saltscan also advantageously be employed; a mixture of sodium cyanate andaqueous ammonia solution may be mentioned as an example.

Naturally occurring organic substances and products obtained therefrom,naturally occurring inorganic substances and products obtainedtherefrom, synthetic organic products, synthetic inorganic productsand/or mixed products consisting of organic and inorganic products canbe used as additives in carrying out process (B). These include,preferably, all those materials which have already been mentioned aspreferred in connection with the description of the additives optionallypresent in the substances to be used according to the invention.

Process (B) is carried out in an aqueous medium, preferably in water.However, it is also possible to replace some of the water by otherdiluents, such as hydrogen sulphide or alcohols, methanol and ethanolbeing mentioned in particular.

The reaction temperatures can be varied within a particular range in thecase of process (B), it being necessary, however, for the temperaturesetting to be adjusted according to the particular reaction phase. Ingeneral, the procedure is first to carry out the polymerisation attemperatures between 30° C. and 70° C., preferably between 40° C. and60° C., for 1 to 4 hours so that an approximately 60% conversion of themonomeric hydrocyanic acid is achieved. Thereafter, the polymerisationis carried out at temperatures between 70° C. and 95° C., preferablybetween 80° C. and 90° C., for a further 4 to 10 hours, whereupon aconversion of about 90 to 95% is achieved. The mixture can then beheated to temperatures of about 100° C. for several hours in order tobring the reaction to completion and to remove hydrocyanic acid stillpresent and any volatile amines or ammonia present.

In general, the reaction according to process (B) is carried out undernormal pressure. However, it is also possible to carry out the reactionunder increased pressure at temperatures between 120° C. and 150° C. Inthis procedure, relatively large amounts of structural defects can beproduced in the process products in a controlled manner.

In carrying out process (B), the basic catalyst is employed in an amountsuch that its proportion is 1 to 15%, preferably 2 to 10%, of themonomeric hydrocyanic acid employed.

The additives are optionally added to the reaction mixture in an amountsuch that their proportion in the end product is between 1 and 95percent by weight, preferably between 5 and 90 percent by weight. Themixture is worked up by customary methods. In general, a procedure isfollowed in which, after removing excess hydrocyanic acid and anyvolatile amines or ammonia present, the reaction mixture is filtered andthe solid product thereby obtained is appropriately washed and dried.

Carbonyl compounds are also employed as starting compounds in process(1). Possible carbonyl compounds here are all compounds with reactivecarbonyl groups. These include, preferably, aldehydes, ketones and ketoesters.

Aldehydes which can particularly preferably be used are formaldehyde,acetaldehyde, hydroxyacetaldehyde, isobutyraldehyde, chloral,hydroxyethylaldehyde, hydroxypivalaldehyde, acrolein, crotonaldehyde,glyoxal, methylglyoxal, furfurol, hydroxymethylfurfurol, glucose,salicylaldehyde and glyceraldehyde.

Furthermore, it is also possible to use, in particular, those compoundswhich release aldehydes, for example formaldehyde, under the reactionconditions. These compounds include, preferably, chloral hydrate andhemi-acetals of formaldehyde, for example those which are derived fromethylene glycol, diethylene glycol, glycerol, methanol, ethanol andpropanol.

Moreover, it is also possible to use, in particular, those aldehydes oraldehyde derivatives which are produced in situ from formaldehyde underthe conditions of the synthesis of formose sugar mixtures. In this case,a procedure is followed in which modified azulmic acids which arecharged with calcium hydroxide, lead hydroxide or other suitablecatalysts or which contain catalytically active substances bonded ascomplexes, are allowed to act on formaldehyde. In this procedure,formaldehyde is converted, in a rapid reaction into C₂ -, C₃ -, C₄ -,C₅ - and C₆ -aldehydes, such as hydroxyacetaldehyde, glyceraldehyde andaldehydes, containing hydroxyl groups, of higher functionality, whichundergo stabilising condensation reactions in situ with amino groups ofthe azulmic acids.

Dihydroxyacetone and cyclohexanone may be mentioned in particular asketones which can preferably be used, and ethyl acetoacetate may bementioned as an example of a keto ester which can preferably be used.

Naturally occurring organic substances and products obtained therefrom,naturally occurring inorganic substances and products obtainedtherefrom, synthetic organic products, synthetic inorganic productsand/or mixed products consisting of organic and inorganic products canbe used as additives in carrying out process (1). These additivesinclude, preferably, all those materials which have already beenmentioned as preferred in connection with the description of theadditives optionally present in the substances to be used according tothe invention.

Process (1) is carried out in an aqueous medium or in anaqueous-alcoholic medium. A preferred possible reaction medium is water,or a mixture of water and an alcohol, such as methanol or ethanol.

The condensation reaction in process (1) is carried out under acid,neutral or basic conditions.

The reaction temperatures can be varied within a substantial range inthe case of process (1). In general, the reaction is carried out attemperatures between 10° C. and 250° C., preferably between 50° C. and150° C.

In general, the reaction in process (1) is carried out under normalpressure. However, it is also possible to carry out the reaction underincreased pressure.

In carrying out process (1), 0.05 to 6 moles, preferably 0.2 to 3 moles,of carbonyl compound, a catalytic amount, or even a larger amount, ofacid or base (about 1 mole of acid or base per 100 parts by weight ofazulmic acid) and optionally an amount of additives such that theirproportion in the end product is between 1 and 95 percent by weight areemployed per mole (relative to the molecular unit ##STR38## with theequivalent weight 54) of modified azulmic acid optionally containingadditives. The mixture is worked up by customary methods. In general, aprocedure is followed in which, after the reaction has ended, thereaction mixture is filtered and the solid product obtained isappropriately washed and dried.

In this connection it should be pointed out that even very small amountsof carbonyl compounds (0.05 to 0.2 mol) are frequently sufficient toobtain substances which have a high stability towards the splitting offof hydrogen cyanide under the influence of heat and under hydrolysisconditions.

If carbonyl compounds such as crotonaldehyde, cyclohexanone or ethylacetoacetate are used for the condensation reaction, as a result of thefairly large cross-section of the molecules of these agents, the rate ofconversion which can be achieved with these topochemical reactions isslower than when compounds with molecules of smaller cross-section areused. In these cases, relatively long reaction times (more than 30hours) and relatively high reaction temperatures are therefore necessaryto achieve adequate stabilising.

In process (2), acid addition salts or complex compounds, optionallycontaining additives, of modified azulmic acids containing from 0.5 to55 percent by weight of ionic groups of the formula ##STR39## andcontaining from 0.5 to 15 percent by weight of groups of the formula##STR40## are subjected to a condensation reaction with carbonylcompounds in an aqueous medium, optionally in the presence of additives.

In the formula (F₁) R preferably represents those substituents whichhave already been mentioned as preferred for R in the description of thesubstances according to the invention.

The acid addition salts or complex compounds of modified azulmic acids(=azulmic acids containing structural defects) to be used as startingmaterials in process (2) can contain 1 to 95 percent by weight,preferably 5 to 90 percent by weight, of additives. Possible additiveshere are naturally occurring organic substances and products obtainedtherefrom, naturally occurring inorganic substances and productsobtained therefrom, synthetic organic products, synthetic inorganicproducts and/or mixed products consisting of organic and inorganicproducts. These additives include, preferably, all those materials whichhave already been mentioned as preferred in the description of theadditives optionally present in the substances to be used according tothe invention.

Preferred possible acids which the acid addition salts, required asstarting materials, of modified azulmic acids can contain, are all thoseacids which have already been mentioned in the description of thesubstances to be used according to the invention. Nitric acid,phosphoric acid, phosphorous acid, chloroacetic acid, dichloroaceticacid, trichloroacetic acid and hydrofluoric acid may be mentioned inparticular.

Preferred salts which the complex compounds, required as startingmaterials, of modified azulmic acids can contain bonded as complexes areall those ammonium salts and metal compounds which have already beenmentioned as preferred in the description of the substances to be usedaccording to the invention. Iron(II) acetate, iron(II) sulphate,iron(III) sulphate, copper acetate, zinc acetate, manganese(II) acetate,cobalt chloride, zinc chloride and tin(II) chloride may be mentioned inparticular.

The acid addition salts, which can be used as starting materials, ofmodified azulmic acids are not yet known. However, they can be preparedby a process in which the modified azulmic acids, optionally containingadditives, accessible by processes (A) or (B) are stirred with theparticular acid in an aqueous medium at room temperature or at elevatedtemperature. The reaction products are isolated by filtration. Thepreparation of some acid addition salts of modified azulmic acids hasalready been disclosed generally in the description of the preparationof modified azulmic acids.

The complex compounds, which can also be used as starting materials inprocess (2), of modified azulmic acids are not yet known. However, theycan be prepared by a process in which the modified azulmic acids,optionally containing additives, accessible by processes (A) or (B) arestirred with the appropriate salts in an aqueous medium at temperaturesbetween 20° C. and 120° C., preferably at 50° C. to 110° C. The mixtureis worked up by customary methods. In general, the reaction products areisolated by filtration. The preparation of some complex compounds ofmodified azulmic acids has already been disclosed generally in thedescription of the preparation of modified azulmic acids.

Possible carbonyl compounds in carrying out process (2) are all thecustomary compounds with reactive carbonyl groups. These include,preferably, aldehydes, ketones and keto esters. All those aldehydes,substances which release an aldehyde, ketones and keto esters which havealready been mentioned in particular in the description of process (1)are particularly preferred.

Naturally occurring organic substances and products obtained therefrom,naturally occurring inorganic substances and products obtainedtherefrom, synthetic organic products, synthetic inorganic productsand/or mixed products consisting of organic and inorganic products canbe used as additives in carrying out process (2). These additivesinclude, preferably, all those materials which have already beenmentioned as preferred in the description of the additives optionallypresent in the substances to be used according to the invention.

Process (2) is carried out in an aqueous medium or in anaqueous-alcoholic medium. A preferred possible reaction medium is water,or a mixture of water and an alcohol, such as methanol or ethanol.

The condensation reaction in process (2) is carried out under acid,neutral or basic conditions.

The reaction temperatures can be varied within a substantial range inthe case of process (2). In general, the reaction is carried out attemperatures between 10° C. and 250° C., preferably between 50° C. and150° C.

In general, the reaction in process (2) is carried out under normalpressure. However, it is also possible to carry out the reaction underincreased pressure.

In carrying out process (2), 0.05 to 6 moles, preferably 0.2 to 3 moles,of carbonyl compound, a catalytic amount, or even a larger amount, ofacid or base (about 1 mole of acid or base per 100 parts by weight ofazulmic acid) and optionally an amount of additives such that theirproportion in the end product is between 1 and 95 percent by weight,preferably between 5 and 90 percent by weight, are employed per mole(relative to the molecular unit ##STR41## with the equivalent weight 54)of acid addition salts or complex compounds, optionally containingadditives, of modified azulmic acid. The mixture is worked up bycustomary methods. In general, a procedure is followed in which, afterthe reaction has ended, the reaction mixture is filtered and the solidproduct obtained is appropriately washed and dried.

A small amount of carbonyl compounds (0.05 to 0.2 mol) is alsofrequently sufficient in carrying out process (2) to obtain substanceswhich have a high stability towards the splitting off of hydrogencyanide under the influence of heat and under hydrolysis conditions.

According to process (3), azulmic acids which are almost free fromstructural defects are subjected to a condensation reaction withcarbonyl compounds in an aqueous medium, optionally in the presence ofadditives.

The azulmic acids which are almost free from structural defects and arerequired as starting materials are known (see Houben-Weyl, volume 8(1952), page 261; German Patent Specification Nos. 662,338 and 949,600).

Possible carbonyl compounds for carrying out process (3) are again allthe customary compounds with reactive carbonyl groups. These include,preferably, aldehydes, ketones and keto esters. All those aldehydes,substances which release an aldehyde, ketones and keto esters which havealready been mentioned in particular in the description of process (1)are particularly preferred.

Naturally occurring organic substances and products obtained therefrom,naturally occurring inorganic substances and products obtainedtherefrom, synthetic organic products, synthetic inorganic productsand/or mixed products consisting of organic and inorganic products canbe used as additives in carrying out process (3). These additivesinclude, preferably, all those materials which have already beenmentioned as preferred in connection with the description of theadditives optionally present in the substances to be used according tothe invention.

Process (3) is carried out in an aqueous medium or in anaqueous-alcoholic medium. A preferred possible reaction medium is water,or a mixture of water and an alcohol, such as methanol or ethanol.

The condensation reaction in process (3) is carried out under acid,neutral or basic conditions.

The reaction temperatures can be varied within a substantial range inthe case of process (3). In general, the reaction is carried out attemperatures between 10° C. and 250° C., preferably between 50° C. and150° C.

In general, the reaction in process (3) is carried out under normalpressure. However, it is also possible to carry out the reaction underincreased pressure.

In carrying out process (3), 0.05 to 6 moles, preferably 0.2 to 3 moles,of carbonyl compound, optionally a catalytic amount, or even a largeramount, of acid or base and optionally an amount of additives such thattheir proportion in the end product is between 1 and 95 percent byweight, preferably between 5 and 90 percent by weight, are employed permole (relative to the molecular unit ##STR42## with the equivalentweight 54) of azulmic acid which is almost free from structural defects.The mixture is worked up by customary methods. In general, a procedureis followed in which, after the reaction has ended, the reaction mixtureis filtered and the solid product obtained is appropriately washed anddried.

A small amount of carbonyl compounds (0.05 to 2 mol) is also frequentlysufficient in carrying out process (3) to obtain substances which have ahigh stability towards the splitting off of hydrogen cyanide under theinfluence of heat and under hydrolysis conditions.

In process (4), hydrocyanic acid is polymerised under hydrolysingconditions in an aqueous medium with the aid of basic catalyts,optionally in the presence of additives, and the reaction products arethen subjected to a condensation reaction with carbonyl compounds,without prior isolation, in an aqueous medium, optionally in thepresence of additives.

Dilute aqueous hydrocyanic acid solutions, to which additives areoptionally admixed, are used as starting materials in this procedure. Ingeneral, solutions with a hydrocyanic acid concentration of between 10and 30%, preferably between 15 and 25%, are used.

Possible basic catalysts for process (4) are organic and inorganic basesand basic salts of the most diverse nature. All those bases or saltswhich have already been mentioned as preferred in connection with thedescription of process (B) can preferably be used here. Mixtures of themost diverse bases or basic salts can also advantageously be employed; amixture of sodium cyanate and aqueous ammonia solution may be mentionedin particular.

Possible additives which can be added to the reaction mixture beforeand/or after the hydrocyanic acid polymerisation are again naturallyoccurring organic substances and products obtained therefrom, naturallyoccurring inorganic substances and products obtained therefrom,synthetic organic products, synthetic inorganic products and/or mixedproducts consisting of organic and inorganic products. These additivesinclude, preferably, all those materials which have already beenmentioned as preferred in connection with the description of theadditives optionally present in the substances to be used according tothe invention.

Possible carbonyl compounds which, in the case of process (4), are addedto the reaction mixture after the hydrocyanic acid polymerisation areagain all the customary compounds with reactive carbonyl groups. Theseinclude, preferably, aldehydes, ketones and keto esters. All thosealdehydes, substances which release an aldehyde, ketones and keto esterswhich have already been mentioned in particular in the description ofprocess (1) are particularly preferred.

Process (4) is carried out in an aqueous medium, preferably in water.However, it is also possible to replace some of the water by otherdiluents, such as hydrogen sulphide or alcohols, methanol and ethanolbeing mentioned in particular.

The reaction temperatures can be varied within a particular range in thecase of process (4), it being necessary, however, for the temperaturesetting to be adjusted according to the particular reaction phase. Ingeneral, the procedure is to first carry out the polymerisation attemperatures between 30° C. and 70° C., preferably between 40° C. and60° C., for 1 to 4 hours, so that an approximately 60% conversion of themonomeric hydrocyanic acid is achieved. Thereafter, polymerisation iscarried out at temperatures between 70° and 95° C., preferably between80° C. and 90° C., for a further 4 to 10 hours, whereupon a conversionof about 90 to 95% is achieved. The mixture can then be heated totemperatures of about 100° C. for several hours in order to bring thereaction to completion and to remove hydrocyanic acid still present andany volatile amines or ammonia present. Thereafter, the condensationreaction with carbonyl compounds is carried out at the temperaturescustomary for this reaction. In general, the reaction is carried out attemperatures between 10° C. and 250° C., preferably between 50° C. and150° C.

In general, the reaction in process (4) is carried out under normalpressure. However, it is also possible to carry out the reaction underincreased pressure at temperatures between 120° C. and 150° C. In thisprocedure, relatively large amounts of structural defects can beproduced in the process products in a controlled manner.

In carrying out process (4), the basic catalyst is employed in an amountsuch that its proportion is 1 to 15%, preferably 2 to 10%, of themonomeric hydrocyanic acid employed. The amount of carbonyl compounds ischosen so that 0.05 to 6 moles, preferably 0.2 to 3 moles, of carbonylcompound are present per mole (relative to the molecular unit ##STR43##with the equivalent weight 54) of azulmic acid formed. The additives areoptionally added to the reaction mixture in an amount such that theirproportion in the end product is between 1 and 95 percent by weight,preferably between 5 and 90 percent by weight. The mixture is worked upby customary methods. In general, a procedure is followed in which,after removing excess hydrocyanic acid and any volatile amines ofammonia present, the reaction mixture is filtered and the solid productthereby obtained is appropriately washed and dried.

In process (5), modified azulmic acids are first reacted with bases inan aqueous medium and the products are then optionally treated withmetal salts and subsequently subjected to a condensation reaction withcarbonyl compounds, optionally in the presence of additives.

Possible modified azulmic acids here are all those azulmic acids whichcontain structural defects and which can also be employed as startingmaterials in carrying out process (1).

Possible bases or basic salts in carrying out process (5) are the mostdiverse inorganic or organic bases and basic salts. Alkali metalhydroxides, such as lithium hydroxide, sodium hydroxide and potassiumhydroxide, alkali metal carbonates, such as sodium carbonate, potassiumcarbonate and potassium bicarbonate, alkali metal sulphides, such assodium sulphide, potassium sulphide and potassium bisulphide, alkalimetal thiosulphates, such as sodium thiosulphate, alkylamines andfurthermore ammonium hydroxide and ammonium salts, such as ammoniumpolysulphides, can preferably be used.

Preferred possible metal salts in carrying out process (5) are all thosemetal salts which have already been mentioned as preferred in connectionwith the description of variant (e) of process (A). Iron(II) acetate,iron(II) sulphate, iron(III) sulphate, copper acetate, zinc acetate,manganese(II) acetate, cobalt chloride, zinc chloride and tin(II)chloride may be mentioned in particular.

Possible additives are again naturally occurring organic substances andproducts obtained therefrom, naturally occurring inorganic substancesand products obtained therefrom, synthetic organic products, syntheticinorganic products and/or mixed products concisting of organic andinorganic products. These additives include, preferably, all thosematerials which have already been mentioned as preferred in thedescription of the additives optionally present in the substances to beused according to the invention.

Possible carbonyl compounds in the case of process (5) are again all thecustomary compounds with reactive carbonyl groups. These include,preferably, aldehydes, ketones and keto esters. All those aldehydes,substances which release an aldehyde, ketones and keto esters which havealready been mentioned in particular in the description of process (1)are particularly preferred.

Process (5) is carried out in an aqueous medium, preferably in water.However, it is also possible to replace some of the water by otherdiluents, such as hydrogen sulphide or alcohols, methanol and ethanolbeing mentioned in particular.

The reaction temperatures can be varied within a substantial range inthe case of process (5). In general, the reaction is first carried outat between 50° C. and 120° C., preferably between 60° C. and 110° C.Thereafter, the condensation reaction with carbonyl compounds is carriedout at the temperatures customary for this reaction. In general, thereaction is carried out at temperatures between 10° C. and 250° C.,preferably between 50° C. and 150° C.

In general, the reaction in process (5) is carried out under normalpressure. However, it is also possible to carry out the reaction underincreased pressure. The latter is advisable, in particular, if ammoniumhydroxide or volatile amines are employed as the bases.

In carrying out process (5), 0.5 to 4 moles of base or basic salt,optionally 1 to 2 moles of metal salt, 0.05 to 6 moles, preferably 0.2to 3 moles, of carbonyl compound and optionally an amount of additivessuch that their proportion in the end product is between 1 and 95percent by weight, preferably between 5 and 90 percent by weight, arepreferably employed per mole (relative to the molecular unit ##STR44##with the equivalent weight 54) of modified azulmic acid. The mixture isworked up by customary methods. In general, a procedure is followed inwhich, after the reaction has ended, the reaction mixture is filteredand the solid product obtained is appropriately washed and dried.However, a procedure is also possible in which the resulting dispersionis first concentrated, an alcohol, such as methanol, is then added, themixture is again concentrated under reduced pressure and, afterrepeating this operation several times, the solid product therebyobtained is filtered off, washed and appropriately dried.

In process (6), modified azulmic acids are first treated with organic orinorganic acids in an aqueous medium and the products are then subjectedto a condensation reaction with carbonyl compounds, optionally in thepresence of additives.

Possible modified azulmic acids here are all those azulmic acids whichcontain structural defects and which can also be employed as startingmaterials in carrying out process (1).

Preferred possible inorganic or organic acids are all those acids whichhave already been listed as preferred in the description of the productsto be used according to the invention.

Possible carbonyl compounds in carrying out process (6) are again allthe customary compounds with reactive carbonyl groups. These include,preferably, aldehydes, ketones and keto esters. All those aldehydes,substances which release an aldehyde, ketones and keto esters which havealready been mentioned in particular in the description of process (1)are particularly preferred.

Naturally occurring organic substances and products obtained therefrom,naturally occurring inorganic substances and products obtainedtherefrom, synthetic organic products, synthetic inorganic productsand/or mixed products consisting of organic and inorganic products canbe used as additives in carrying out process (6). These additivesinclude, preferably, all those materials which have already beenmentioned as preferred in the description of the additives optionallypresent in the substances to be used according to the invention.

Process (6) is carried out in an aqueous medium, preferably in water.However, it is also possible to replace some of the water by otherdiluents, such as alcohols, methanol and ethanol being mentioned inparticular.

The reaction temperatures can be varied within a substantial range inthe case of process (6). In general, the treatment of the azulmic acidswith acids is carried out at temperatures between 0° C. and 200° C.,preferably between 20° C. and 120° C. Thereafter, the condensationreaction with carbonyl compounds is carried out at the temperaturescustomary for this reaction. In general, the reaction is carried out attemperatures between 10° C. and 250° C., preferably between 50° C. and150° C.

In general, the reaction in process (6) is carried out under normalpressure. However, it is also possible to carry out the reaction underincreased pressure.

In carrying out process (6), a catalytic amount, or even a largeramount--preferably 1 to 4 moles--of inorganic or organic acid, 0.05 to 6moles, preferably 0.2 to 3 moles, of carbonyl compound and optionally anamount of additives such that their proportion in the end product isbetween 1 and 95 percent by weight, preferably between 5 and 90 percentby weight, are employed per mole (relative to the molecular unit##STR45## with the equivalent weight 54) of modified azulmic acid. Themixture is worked up by customary methods. In general, a procedure isfollowed in which, after the reaction has ended, the reaction mixture isfiltered and the solid product obtained is appropriately washed anddried. Any excess acid is still present in the products thus formed canbe converted into the corresponding ammonium salts by gassing withammonia, the reaction advantageously being carried out in the solidphase in a fluidised bed.

In process (7), azulmic acids which are almost free from structuraldefects are subjected to a condensation reaction with carbonyl compoundsin an aqueous medium, in the presence of hydrolytically degradablenaturally occurring substances and in the presence of an acid.

Possible hydrolytically degradable naturally occurring substances hereare all those naturally occurring substances which are completely orpartially degraded under the influence of an acid. These include,preferably, celluloses, hemicelluloses, sugars, lignin, polymericquinones, wood flour, vegetable material, polypeptides, such as gelatinand wool, and furthermore yeast proteins, algal compositions and peatcompositions.

Possible acids are all the sufficiently strong organic or inorganicacids. Phosphoric acid and phosphorous acid can be preferably used.

Possible carbonyl compounds in carrying out process (7) are again allthe customary compounds with reactive carbonyl groups. These include,preferably, aldehydes, ketones and keto esters. All those aldehydes,substances which release an aldehyde, ketones and keto esters which havealready been mentioned in particular in the description of process (1)are particularly preferred.

Process (7) is carried out in an aqueous medium, preferably in water.However, it is also possible to replace some of the water by otherdiluents, such as alcohols, methanol and ethanol being mentioned inparticular.

The reaction temperatures can be varied within a substantial range incarrying out process (7). In general, the reaction is carried out attemperatures between 10° C. and 250° C., preferably between 50° C. and150° C.

In general, the reaction in process (7) is carried out under normalpressure. However, it is also possible to carry out the reaction underincreased pressure.

In carrying out process (7), a catalytic amount, or even a largeramount--preferably 1 to 4 moles--of inorganic or organic acid, 0.05 to 6moles, preferably 0.2 to 3 moles, of carbonyl compound and an amount ofhydrolytically degradable naturally occurring substances such that theirproportion in the end product is between 1 and 95 percent by weight,preferably between 5 and 90 percent by weight, are preferably employedper mole (relative to the molecular unit ##STR46## with the equivalentweight 54) of azulmic acid. In this procedure, structural defects areproduced with simultaneous hydrolytic degradation of the particularnaturally occurring substances employed and with simultaneousstabilising of the azulmic acids by condensation with carbonylcompounds. If 0.2 to 80% strength phosphoric acid or phosphorous acidand polypeptides are used, the latter are split into aminoacid mixtures.

Because of its numerous amino groups, the azulmic acid bonds about 0.3to 0.4 mol of acid, for example phosphoric acid or phosphoric acid,whilst the phosphoric acid salts of the aminoacids or those of theoligopolypeptides, or the other low-molecular degradation products ofthe naturally occurring substances employed are frequently fixed by theazulmic acid matrix in a large amount, even when they are water-soluble.Excess acid, for example phosphoric acid, can be precipitated on theazulmic acid matrix as calcium phosphate by adding calcium hydroxide. Ifhydrolysed sugars and oligosaccharides are present in this case, theyare absorbed onto the azulmic acid in the form of their calciumcomplexes, which are usually sparingly soluble. The process productsobtained by this process can be stored for a relatively long periodwithout unpleasant odours being formed, as is otherwise the case whennaturally occurring substances such as oligopeptides, peptide/sugarmixtures and the like are degraded by biological processes. Substancesof this type are outstandingly suitable for the fertilisation of plants.

Isolation of the process products is carried out by customary methods,in general by filtration.

If free amino groups are still present in the products prepared byprocesses (1) to (7), these products can be converted into thecorresponding acid-addition salts by treatment with inorganic or organicacids. In this case, a procedure is followed in which the products arestirred with the particular acid in an aqueous medium, optionally atelevated temperature. The reaction products are isolated by filtration.

If free carboxyl groups are still present in the products prepared byprocesses (1) to (7), these products can be converted into thecorresponding salts by treatment with bases. In this case, a procedureis followed in which the products are stirred with the particular basein an aqueous medium, optionally at elevated temperature. The reactionproducts are isolated by filtration.

Furthermore, products according to the invention can also be convertedinto complex compounds. In this case, a procedure is followed in whichthe products are stirred with a metal salt in an aqueous medium,optionally at elevated temperature. The reaction products are isolatedby filtration. They are very suitable for the fertilisation of plants.

The processes can be carried out according to a number of specificvariants. Thus, a preferred embodiment of process (2) consists of aprocedure in which structural defects are produced in azulmic acid whichis almost free from structural defects using nitric acid according tovariant (a) of process (A), the reaction temperature being keptrelatively low, preferably between 20° C. and 30° C., during thisprocedure, and the modified azulmic acids thereby formed in atopochemical reaction, in which 30 to 50% of the amino groups presentare in the form of ionic groups of the formula ##STR47## are subjectedto a condensation reaction with carbonyl compounds, if appropriate afterprior gassing with ammonia, in an aqueous medium. The gassing withammonia, in which traces of free nitric acid are converted into ammoniumnitrate, is appropriately carried out in the solid phase in a fluidisedbed. The poducts formed in this procedure are valuable fertilisers,because both the organically bonded nitrogen of the azulmic acids andthe inorganically bonded nitrogen of the ammonium salts are available toplants.

A further preferred embodiment of process (2) consists of a procedure inwhich structural defects are produced in azulmic acid which is almostfree from structural defects using phosphoric acid or phosphorous acidaccording to variant (a) of process (A), the reaction temperature beingkept relatively low, preferably between 20° C. and 55° C., during thisprocedure, and the modified azulmic acids thereby formed in atopochemical reaction, which have only a few F₂ structural defects andwhich contain phosphoric acid or phosphorous acid bonded in the form ofa salt, are subjected to a condensation reaction with carbonylcompounds, if appropriate after prior gassing with ammonia. The gassingwith ammonia is again appropriately carried out in the solid phase in afluidised bed. In this case also, very active fertilisers are obtained.

A preferred embodiment of process (1) consists of a procedure in whichstructural defects are produced in azulmic acid which is almost freefrom structural defects using 1 to 4 mols of 1 molar phosphoric acid,the excess phosphoric acid is then precipitated as calcium phosphate byadding calcium chloride, as magnesium phosphate by adding magnesiumchloride or as ammonium magnesium phosphate by adding ammonia andmagnesium salts, and thereafter the reaction product is subjected to acondensation reaction with carbonyl compounds, optionally in thepresence of additives. Particularly preferred additives in this case arevegetable ashes, insoluble polyquinones, addition products andcondensation products of benzoquinone with amines, in particular withammonia, and furthermore lignin-sulphonic acids, humic acids, variousfly ashes, bauxite, aluminium oxide, cobalt molybdate, silicon dioxide,active charcoal, zirconium dioxide, nickel oxide, palladium oxide andbarium oxide. Further preferred additives are sugars, such as canesugar, and other sugars which contain no free aldehyde groups, orformose sugar mixtures prepared from formaldehyde. These most diversetypes of sugars can be fixed in the channels and pores of the solidazulmic acid matrices. Moreover, the various sugars can also be absorbedonto the azulmic acids in the form of their calcium complexes, which areusually sparingly soluble.

A further embodiment of process (1) consists of a procedure in whichstructural defects are produced in azulmic acids which are almost freefrom structural defects with the aid of strong bases, for examplepotassium hydroxide, according to variant (b) of process (A), relativelylong reaction times being observed, and the modified azulmic acidsthereby formed in a topochemical reaction, which have polyelectrolytecharacter, are subjected to a condensation reaction with carbonylcompounds, optionally in the presence of additives.

Another preferred embodiment of process (1) consists of a procedure inwhich structural defects are produced in azulmic acids which are almostfree from structural defects using gaseous ammonia under pressure in anaqueousalcoholic medium at temperatures between 120° C. and 140° C.,according to variant (b) of process (A), and the modified azulmic acidsthereby formed in a topochemical reaction, which have a high content ofammonium carboxylate groups, are subjected to a condensation reactionwith carbonyl compounds, optionally in the presence of additives.

Another preferred embodiment of process (1) consists of a procedure inwhich structural defects are produced in azulmic acids which are almostfree from structural defects using waterglass according to variant (b)of process (A) and the modified azulmic acids, charged with potassiumions or sodium ions, thereby formed in a topochemical reaction, thesaponifiable nitrile groups of which act as latent acids and precipitatesilicic acids, are subjected to a condensation reaction with carbonylcompounds, optionally in the presence of additives. The silicic acidswhich have precipitated are absorbed, in fine distribution, onto thereaction products. Any excess sodium silicate or potassium silicatepresent can be precipitated by simple gassing of the particulardispersions with carbon dioxide, or can be precipitated in aparticularly advantageous manner by adding phosphoric acid or calciumchloride mixed with potassium phosphates or sodium phosphates or calciumsilicates.

Yet another preferred embodiment of process (1) consists of a procedurein which structural defects are produced in azulmic acids which arealmost free from structural defects using 25% strength aqueous ammoniasolution at room temperature in the course of 6 to 20 hours, accordingto variant (b) of process (A), and the modified azulmic acids,containing ammonium salts, thereby formed in a topochemical reaction aresubjected to a condensation reaction with carbonyl compounds, optionallyin the presence of additives.

It is frequently also appropriate to treat moist azulmic acidsstabilised with carbonyl compounds and optionally containing additiveswith ammonia gas, with simultaneous gassing with carbon dioxide,structural defects being produced. Ammonia and carbon dioxide therebypenetrate into the azulmic acid matrix to a considerable extent as smallmolecules. In the case of gassing with ammonia in a fluidised bed, forexample, the unstable ammonium carbaminates, ammonium bicarbonates and,if ammonia and carbon dioxide are introduced in the absence of water,ammonium carbamate of the formula ##STR48## are obtained, fixed in thechannels of the azulmic acid. In this form, the ammonium carbamate has areduced liability to decompose at room temperature. It provides anitrogen fertiliser for plants.

A further important embodiment of process (2) consists of a procedure inwhich azulmic acid complexed with calcium hydroxide is reacted withsucrose, sugars, glucose or formose formulations which are prepared bycondensation of formaldehyde with calcium hydroxide. If, for example,sucrose is used in this procedure, azulmic acids are formed which arecharged with sucrose-calcium oxide complexes of the composition 3CaO.C₁₂ H₂₂ O₁₁.

If modified azulmic acids are employed as starting materials in theprocesses described, it is not absolutely necessary to isolate themafter their preparation. Rather, it is by all means possible first tosynthesise the modified azulmic acids and then directly to subject theseto a condensation reaction with carbonyl compounds, without priorisolation.

In the case of the processes described, it is possible to carry out theproduction of structural defects and the simultaneous or subsequentcondensation with carbonyl compounds not only in water but also in thosehydrolysing media in which some of the water has been replaced byhydrogen sulphide, or in which the water contains sodium sulphides,ammonium polysulphides or potassium bisulphide. If in such cases theprocess is carried out at temperatures between 70° C. and 100° C., smallamounts of hydrocyanic acid split off are converted into carbonoxysulphide and ammonia, structural defects being produced at the sametime.

The number of structural defects in the products according to theinvention can optionally be increased by those methods which havealready been described in connection with the preparation of modifiedazulmic acids.

It is frequently advantageous to treat the products with bases aftertheir preparation, in order, for example, to convert metal saltscontained therein into metal hydroxides or oxides, or, for example, toallow aldehydes still contained therein to react completely. For thispurpose, the products are preferably treated or gassed with ammonia orprimary or secondary amines, or reacted with hydrazine hydrate, aqueouscyanamide solutions or aqueous ammonia solution. In the case of theaction of ammonia, small amounts of formaldehyde still contained in theproducts condensed with formaldehyde, for example, are converted intohexamethylenetetramine or hexahydrotriazines. An after-treatment with25% strength aqueous ammonia solution is frequently advisable.

As already mentioned, even a relatively small amount of carbonylcompound is frequently sufficient to obtain products which arerelatively stable towards the splitting off of hydrocyanic acid, bothunder the influence of heat and under hydrolysis conditions. Ifformaldehyde is used for the stabilising, hydrocyanic acid thereby splitoff can be trapped particularly readily by the formation ofwater-soluble cyanohydrins from hydrocyanic acid and formaldehyde.

If a sufficient amount of carbonyl compounds is used for the stabilisingin the reactions described, products are formed from which hydrogencyanide is split off neither in the dry state nor in the moist state atroom temperature or even at higher temperatures. This is shown, interalia, by the fact that in contrast to azulmic acids which have not beenstabilised, the products to be used according to the invention arecompletely inert to standardised dried yeast formulations and in no wayreduce the activity of the yeast during the alcoholic fermentation ofcane sugar under mild conditions. Thus, the fermentation of cane sugarwith standardised dry air in buffered aqueous solution at 35° C. is notimpaired by azulmic acid, condensed with formaldehyde, simultaneouslypresent, whilst a considerably retarded conversion of cane sugar isfound when the same test is carried out in the presence of azulmic acidswhich have not been stabilised. Thus, in the last case, the yeastenzymes are so severely deactivated by the cyanide ions contained in thereaction mixture that the alcoholic fermentation is drasticallyinhibited.

The azulmic acids stabilised by condensation with carbonyl compoundsparticularly those containing structural defects, and acid additionsalts and complex compounds thereof and mixed products thereof withadditives are suitable as agrochemical agents (=agrochemicals). By thesethere are to be understood agents which can be used for the most diversepurposes in agriculture and horticulture.

Thus, the substances according to the invention are suitable, forexample, as fertilisers both for supplying plants with micronutrientsand for supplying plants with macronutrients; they are particularlysuitable as fertilisers having a long-term action. Those substancesaccording to the invention which contain ions required by plants, suchas ammonium ions, lithium ions, sodium ions, potassium ions, berylliumions, magnesium ions, calcium ions, strontium ions, barium ions,aluminium ions, zinc ions, manganese ions, nickel ions, cobalt ions oriron ions, are of particular interest in this context.

Those substances according to the invention which contain anions such aschloride, nitrate, sulphate and/or phosphate are also of particularinterest as fertilisers.

Particularly preferred fertilisers are those substances according to theinvention which contain several of the above-mentioned types of ionsside by side. Examples which may be mentioned are substances whichcontain both potassium and/or ammonium ions and nitrate and/or phosphateions.

Furthermore, those substances according to the invention which alsocontain organic substances, optionally in addition to nutrient ions, areof particular interest as fertilisers. Substances which may be mentionedin particular in this context are wood flour, lignin powder,lignin-sulphonic acids, ammonified lignin-sulphonic acids, humus, humicacids, ammonified humic acids, peat, proteins and degradation products,for example hydrolysis products, of yeast, algae material (alginates),polypeptides, such as wool and gelatine, fish-meal and bone-meal, andfurthermore amino acids, oligopolypeptides, pectins, monosaccharides,such as glucose and fructose, disaccharides, such as sucrose,oligosaccharides, polysaccharides, such as starch and cellulose, andalso hemicelluloses, homogenised materials of vegetable and animalorigin, active charcoals and ashes which are obtainable by partialoxidation, complete oxidation or combustion of organic substances formedby photosynthesis or of customary fuels, wherein fir ash, broom ash, ashof Serbian spruce, oak ash, birch ash, beech ash, willow ash and tobaccoleaf ash, may be mentioned.

Those substances to be used according to the invention which alsocontain commercially available fertilisers, optionally in addition tonutrient ions, are additionally preferably to be used as fertilisers.Commercially available fertilisers of this type which may be mentionedin this connection are super phosphate, basic slag, Rhenania phosphate,phosphorite, calcium cyanamide, calcium ammonium nitrate, Leunasaltpeter, potassium phosphates, potassium nitrate and ammonium nitrate,and furthermore urea/formaldehyde condensation products,urea/crotonaldehyde condensation products, urea/isobutyraldehydecondensation products and condensation products of dicyandiamide,melamine or oxamide and aldehydes, such as formaldehyde, acetaldehyde,crotonaldehyde or isobutyraldehyde.

Those substances according to the invention which also containbiologically active garden mould, optionally in addition to nutrients,can also preferably be used as fertilisers.

Furthermore, the substances according to the invention are suitable asagents for improving soil. Those substances according to the inventionwhich contain wood powder or powdered vegetable material can preferablybe used for this purpose. Azulmic acids which can also preferably beused as agents for improving soil are those which have first beenpartially (only about every fourth amino group, in statisticaldistribution) condensed with carbonyl compounds, in particularformaldehyde, and then are reacted with formaldehyde in the presence ofcalcium hydroxide. Under these conditions, glycolaldehyde (C₂-aldehyde), glyceraldehyde (C₃ -aldehyde) and further C₄ -C₇-hydroxyaldehydes are formed very rapidly in situ from monomericformaldehyde, and can undergo condensation reactions with remainingamino groups on the azulmic acids and can likewise lead to partialstabilising of the substances according to the invention. Because of thetackiness of the concomitant higher-molecular caramellised sugarsobtained, these products can be spray-dried completely free fromformaldehyde. They are brown-black, humus-like substances with a friablestructure, which are of interest both as agents for improving soil andas plant nutrients. The sugar mixtures absorbed onto the matrix in thisprocedure can be complexed with relatively large amounts of calciumhydroxide or magnesium hydroxide, sugar complexes being formed such asare known, for example, with sucrose, 3 moles of calcium oxide beingbonded per mole of sucrose. In the case of the substances containingazulmic acid, formose and calcium hydroxide, the low solubility ofcomplexes of this type advantageously impedes rapid washing out of thesugars when the substances are applied in the agricultural sector.

Those substances to be used according to the invention which have a highcontent of structural defects have a polyelectrolyte character, and inthe soil can function as fertilizers with ion exchanger properties. Inthis case, the ions required by plants, for example potassium ionsand/or ammonium ions, are released into the earth or onto the substrate,whilst other ions are bonded.

As a result of the high absorbency and the good capacity for formingcomplexes, the substances according to the invention can also be usedfor fixing harmful substances in soil. Thus, with the aid of thesubstances according to the invention, it is possible, for example, tobond undesired heavy metal ions present in soil, for example ions oflead and of mercury, so firmly that damage to plants need no longer befeared. Furthermore, oil pollution, overdoses of agents for plantprotection or excessively high salt concentrations in substrates can beremoved by adding substances to be used according to the invention.

Substances according to the invention which also contain peat, inaddition to other plant nutrients, can be used in a simple mannerindustrially, by adding binders, such as starch, degraded celluloses,alginates and Pectin substances, for the production of compressed peatpots for the horticultural business. In this case, it is appropriate forthe proportion by volume of white peat to black peat in the substrate tobe about 1:1.

Substances according to the invention which contain, in addition toother plant nutrients, about 20 to 40 percent by weight of peat are alsovery suitable for covering soils and substrates as well as seed rows,since the black colour of the substances to be used according to theinvention ensures a good earth-like appearance, surface crusting isprevented and more rapid germination in seed rows is effected.

Substances to be used according to the invention which contain peat arealso suitable for preventing or weakening odours arising duringdecomposition processes.

Substances to be used according to the invention which also containpeat, in addition to other plant nutrients, can be converted, by addingstarch adhesives, hemicelluloses or alignates, into shaped,moisture-retaining materials which are impermeable to air and aresuitable as packing materials for the transportation of plants.

Substances to be used according to the invention are also suitable forprotecting plants or parts of plants from pests, such as, for example,caterpillars. For example, if a spray liquor based on a substancecontaining 4-12 percent by weight of structural defects of the formula##STR49## mixed with 10 percent by weight of caramellised formose per100 percent by weight of product according to the invention is used forspraying the foliage of fruit trees, an adhesive, sticky layer is formedon the leaves which, on the one hand, reduces damage to the leaves bypests, for example caterpillars, and on the other hand, provides a topdressing.

The substances according to the invention can be employed as such, or intheir formulations, for supplying plants with nutrients or as agents forimproving soil.

The substances to be used according to the invention can be converted tothe customary formulations, such as emulsions, wettable powders,suspensions, powders, dusting agents, foams, pastes, granules,suspension-emulsion concentrates, seed-treatment powders, natural andsynthetic materials impregnated with active compound or very finecapsules in polymeric substances and in coating compositions, for use onseed.

These formulations may be produced in known manner, for example bymixing the active compounds with extenders, that is to say liquid and/orsolid diluents, carriers, optionally with the use of surface-activeagents, that is to say emulsifying agents and/or dispersing agentsand/or foam-forming agents. In the case of the use of water as anextender, organic solvents can, for example, also be used as auxiliarysolvents.

As liquid diluents or carriers, especially solvents, there are suitablein the main, aromatic hydrocarbons, such as xylene, toluene or alkylnaphthalenes, chlorinated aromatic or chlorinated aliphatichydrocarbons, such as chlorobenzenes, chloroethylenes or methylenechloride, aliphatic or alicyclic hydrocarbons, such as cyclohexane orparaffins, for example mineral oil fractions, alcohols, such as butanolor glycol as well as their ethers and esters, ketones, such as acetone,methyl ethyl ketone, methyl isobutyl ketone or cyclohexanone, orstrongly polar solvents, such as dimethylformamide anddimethylsulphoxide, as well as water.

As solid carriers there may be used ground natural minerals, such askaolins, clays, talc, chalk, quartz, attapulgite, montmorillonite ordiatomaceous earth, and ground synthetic minerals, such ashighly-dispersed silicic acid, alumina and silicates. As solid carriersfor granules there may be used crushed and fractionated natural rockssuch as calcite, marble, pumice, sepiolite and dolomite, as well assynthetic granules of inorganic and organic meals, and granules oforganic material such as sawdust, coconut shells, maize cobs and tobaccostalks.

As emulsifying and/or foam-forming agents there may be used non-ionicand anionic emulsifiers, such as polyoxyethylene-fatty acid esters,polyoxyethylene-fatty alcohol ethers, for example alkylaryl polyglycolethers, alkyl sulphonates, alkyl sulphates, aryl sulphonates as well asalbumin hydrolysis products. Dispersing agents include, for example,lignin sulphite waste liquors and methylcellulose.

Adhesives such as carboxymethylcellulose and natural and syntheticpolymers in the form of powders, granules or latices, such as gumarabic, polyvinyl alcohol and polyvinyl acetate, can be used in theformulations.

It is possible to use colorants such as inorganic pigments, for exampleiron oxide, titanium oxide and Prussian Blue, and organic dyestuffs,such as alizarin dyestuffs, azo dyestuffs or metal phthalocyaninedyestuffs, and trace nutrients, such as salts of iron, manganese, boron,copper, cobalt, molybdenum and zinc.

The formulations in general contain from 0.1 to 95 percent by weight ofactive compound, preferably from 0.5 to 90 percent by weight.

The substances according to the invention can be in the formulations asmixtures with other fertilisers or pesticidal active compounds.

When used as fertilisers or as agents for improving soil, the activecompounds can be applied either in the form of the substances themselvesor in the form of their formulations or the use forms preparedtherefrom, such as ready-to-use emulsions, foams, suspensions, powders,pastes and granules. They are applied in accordance with the methodscustomary in agriculture and in horticulture, for example by directintroduction into the soil, by watering, spraying, atomising,scattering, dusting and the like. The following may be mentioned asspecial types of application: root application, leaf application, steminjection and bark application. In the case of root application, thefertiliser can either be mixed with the culture substrate or beintroduced into furrows in the soil. Furthermore, it is possible tointroduce the fertiliser into the lower root region by means of afertiliser lance or through punched or drilled holes. Application to theleaf is as a rule effected by spraying the plants with a fertiliserformulation or by dipping plants or parts of plants into a fertiliserformulation. In the case of stem injection, the fertiliser is directlyintroduced into the plants through bore-holes or tree trunks orbranches. Bark application can be effected by spraying the bare woodwith the fertiliser formulation, or by placing bands, for example oftextile, paper or foam plastic, impregnated with nutrients, on treetrunks or branches - if appropriate after partial or complete removal ofthe layer of bark or cork in the treatment zone. Application to the barkby means of pastes containing nutrients is also possible.

The amount of active substances employed can vary within a relativelywide range. When the substances are used as fertilisers or as agents forimproving soil, the amount depends essentially on the nature of the soiland on the nutrient requirement of the particular plants. In general,the amounts of active compound applied are between 0.1 and 200 kg/ha,preferably between 1 and 100 kg/ha. If the substances according to theinvention are used for other purposes, for example for coveringsubstrates, for the production of packing materials for plants, forprotecting plants or parts of plants, for the production of compressedpeat pots or for bonding undesired odours, the amount of active compoundemployed is adjusted to suit the particular requirement.

The good activity of the substances according to the invention asfertilisers can be seen from the examples which follow.

Preparations List

Preparation (A)=azulmic acid stabilised with formaldehyde, in whichabout 78% of the amino groups contained therein were condensed.Composition: 35.3% C; 4.0% H; 39.1% N; 21.5% O.

Preparation (B)=azulmic acid, in which about 7% by weight of structuraldefects of the formula ##STR50## were first produced by saponification,and then about 13% by weight of phosphoric acid was fixed onto thematrix. Composition: 33.3% C; 4.3% H; 28.1% N; 4.1% P; 3.2% K.

Preparation (C)=azulmic acid, in which structural defects of the formula##STR51## were first produced by acid saponification, and then about12.5% by weight of phosphoric acid were fixed onto the matrix.Composition: 36.1% C; 3.9% H; 32.1% N; 24.1% O; 3.9% P.

Preparation (D)=azulmic acid stabilised with formaldehyde

Preparation (E)=azulmic acid stabilised with formaldehyde

Preparation (F)=azulmic acid stabilised with formaldehyde

Preparation (G)=azulmic acid stabilised with formaldehyde

EXAMPLE A Fertilisation test/test in the open

Test plant: grass (lawn)

Areas of lawn 1.5 m² were fertilised on the surface with the particularamount of preparation desired.

Evaluation was carried out after 6 weeks. The additional growth and theappearance of the area of grass were assessed in each case. The ratingshad the following meanings:

1=very heavy additional growth, dark green

2=heavy additional growth, dark green

3=average additional growth, green

4=slight additional growth, light green

5=control (without fertilisation)

The active compound preparations, amounts applied and test results canbe seen from the table which follows:

                  TABLE A                                                         ______________________________________                                        Fertilisation test/test in the open                                                           Amount of                                                            Nitrogen preparation                                                   Prepara-                                                                             per m.sup.2                                                                            in g per    Ratings                                           tion   [g]      1 m.sup.2                                                                             1.5 m.sup.2                                                                         Repeat 1                                                                             Repeat 2                                                                             φ                             ______________________________________                                        A      10       25.6    38.4  5      4      4.5                                      25       64      96    4      3      3.5                                      50       128     192   3      2-3    2.8                                      100      256     384   1-2    1      1.3                               B      10       31.2    46.8  4-5    4-5    4.5                                      25       78      117   3-4    3-4    3.5                                      50       156     234   2      2      2                                        100      312     468   1      1-2    1.3                               C      10       35.6    53.4  4      4-5    4.3                                      25       89      133.5 3      4      3.5                                      50       178     267   1-2    2      1.8                                      100      356     534   2      2      2                                 Control                                                                              --       --      --    5      5      5                                 ______________________________________                                    

EXAMPLE B Fertilisation test/test in the open

Test plant: potted chrysanthemums

Type of soil: sandy loam+30% by volume of peat per 1.5 liter vessel

A base fertiliser was first added to each pot, and in particular 0.25 gof phosphorus pentoxide in the form of superphosphate and 0.4 g ofpotassium oxide in the form of potassium magnesia were added per literof soil.

The particular amount desired of the test preparation was then placed onthe surface of the soil.

Evaluation was carried out after 3 months. The additional growth and theappearance of the plants (leaves) were evaluated in each case. Theratings had the following meanings:

1=dark green

2=medium green

3=light to medium green

4=light green

5=light green to yellow

The active compound preparations, amounts applied and test results canbe seen from the table which follows:

                                      TABLE B                                     __________________________________________________________________________    Fertilisation test/test in the open                                                           Amount of                                                          Nitrogen                                                                           Amount of                                                                           preparation   Leaf colour                                     Prepara-                                                                           [g/l of                                                                            preparation                                                                         per 1.5 l                                                                           Growth heigth                                                                             anthocyanin                                                                          Leaf                                 tion soil]                                                                              g/l of soil                                                                         of soil                                                                             in cm   Rating                                                                            coloration                                                                           damage                               __________________________________________________________________________    A    0.5  1.28  1.9   18      2   +      slight                                    1    2.56  3.8   19      2   +      "                                         2.5  6.39  9.6   20      1   +      severe                                    5    12.78 19.2  20      1   +      "                                    B    0.5  1.56  2.3   19      3   +      --                                        1    3.12  4.7   22      3   +      slight                                    2.5  7.78  11.7  23      2-3 +      severe                                    5    15.56 23.4  16      2   +      very severe                          C    0.5  1.78  2.7   25      3   +      --                                        1    3.56  5.3   26      2   +      --                                        2.5  8.89  13.3  30      2   +      --                                        5    17.80 26.7  27      1-2 +      --                                   --   --   --    --    18      5   +      --                                   Control                                                                       __________________________________________________________________________

EXAMPLE C Fertilisation test/test in the open

Test plant: "Berliner tiergarten" grass, 3 g per vessel

Type of soil: sandy loam+30% by volume of peat

Vessel: plastic pots of 10 liter capacity, filled with 8.5 kg of soil

A base fertiliser was first added to each pot, and in particular 0.25 gof phosphorus pentoxide in the form of superphosphate and 0.40 g ofpotassium oxide in the form of potassium magnesia were added per literof soil.

The particular amount desired of the test preparation was then placed onthe surface of the soil.

Evaluation was carried out after 7 weeks and 11 weeks. The additionalgrowth and the appearance of the plants were evaluated in each case. Theratings had the following meanings:

1=dark green

2=medium green

3=medium green to yellow

The active compound preparations, amounts applied and test results canbe seen from the table which follows.

                                      TABLE C                                     __________________________________________________________________________    Fertilization test/test in the open                                                      Amount of                                                                Nitrogen                                                                           prepara-                                                                            Dry substance                                                      g per 1 of                                                                         tion g per                                                                          g/vessel                                                     Preparation                                                                         soil 1 of soil                                                                           1st cut                                                                           2nd cut 1st + 2nd                                                                           Rating                                     __________________________________________________________________________    A     0.5  1.28  7.2 4.4     11.6  3                                                1.0  2.56  10.3                                                                              6.6     16.9  3                                                2.5  6.39  8.5 11.3    19.8  3                                                5.0  12.78 3.9 7.2     11.1  2                                          B     0.5  1.56  10.4                                                                              5.1     15.6  3                                                1.0  3.12  13.9                                                                              8.2     22.1  2                                                2.5  7.76  23.2                                                                              9.9     33.1  1-2                                              5.0  15.56 --  --      --    --                                         C     0.5  1.78  5.2 5.4     10.6  3                                                1.0  3.56  6.4 3.9     10.3  3                                                2.5  8.89  11.4                                                                              6.3     17.7  2                                          Control                                                                             --   --    4.2 2.8      7.0  3                                          __________________________________________________________________________

EXAMPLE D Fertilisation test/test in the open and in a greenhouse

Test plant: "Berliner Tiergarten" grass, 3 g per vessel

Type of soil: sandy loam/30% by volume of peat

Vessel: plastic pots of 10 liter capacity, filled with 8.5 kg of soil

A base fertiliser was first added to each pot, and in particular 0.25 gof phosphorus pentoxide in the form of superphosphate and 0.40 g ofpotassium oxide in the form of potassium magnesia were added per literof soil.

The particular amount desired of the test preparation was then placed onthe surface of the soil.

Evaluation was carried out after 7 weeks, 11 weeks, 4 months, 51/2months, 8 months and 101/2 months. The cut weights were determined ineach case. The vessels stood in the open until after the second cut andthen in a greenhouse.

The active compound preparations, amounts applied and test results canbe seen from the table which follows.

                                      TABLE D                                     __________________________________________________________________________    Fertilization test/test in the open and in a greenhouse                       g of N   Yield average amount, in g, of dry substance per vessel              per 1    Individual cut weights    Total cut weights                          Prepara-                                                                           of  1st cut                                                                           2nd cut                                                                            3rd cut                                                                            4th cut                                                                           5th cut                                                                           6th cut                                                                           1st                                                                              2nd                                                                              3rd                                                                              4th                                                                              5th                                                                              6th                         tion soil                                                                              17.9.74                                                                           16.10.74                                                                           23.11.74.                                                                          14.2.74                                                                           1.4.75                                                                            24.6.75                                                                           cut                                                                              cut                                                                              cut                                                                              cut                                                                              cut                                                                              cut                         __________________________________________________________________________    --   --  4.2 2.8  3.3  1.8 1.4 4.8 4.2                                                                              7.0                                                                              10.3                                                                             12.1                                                                             13.5                                                                             18.3                        (without                                                                      fertilizer)                                                                   A    0.5 7.2 4.4  4.4  2.3 2.7 8.2 0.5                                                                              7.7                                                                              12.1                                                                             16.5                                                                             18.8                                                                             21.5                             1   10.3                                                                              6.6  6.0  4.1 5.9 10.8                                                                              10.3                                                                             16.9                                                                             22.9                                                                             27.0                                                                             32.9                                                                             43.7                             2.5 8.5 11.3 7.2  3.6 6.3 16.7                                                                              8.5                                                                              19.8                                                                             27.0                                                                             30.6                                                                             36.9                                                                             53.6                        B    0.5 10.4                                                                              5.1  4.8  2.7 3.0 8.3 10.4                                                                             15.5                                                                             20.3                                                                             23.0                                                                             26.0                                                                             34.3                             1   13.9                                                                              8.2  5.6  3.6 4.0 9.0 13.9                                                                             22.1                                                                             27.7                                                                             31.3                                                                             35.3                                                                             44.3                             3.5 23.2                                                                              9.9  8.2  2.7 6.2 20.1                                                                              23.2                                                                             33.1                                                                             41.3                                                                             44.0                                                                             50.2                                                                             70.3                        C    0.5 5.2 5.4  3.4  2.4 2.1 6.0 5.2                                                                              10.6                                                                             14.0                                                                             16.4                                                                             18.5                                                                             24.5                             1   6.4 3.9  4.5  2.9 3.2 6.7 6.4                                                                              10.3                                                                             14.8                                                                             17.7                                                                             20.9                                                                             27.6                             2.5 11.4                                                                              6.3  6.4  3.3 6.1 10.4                                                                              11.4                                                                             17.7                                                                             24.1                                                                             27.4                                                                             33.6                                                                             43.9                        __________________________________________________________________________

EXAMPLE E Fertilisation test/test in the open

Test plant: potted chrysanthemums; variety: Yellow Delaware

Type of soil: sandy loam+30% by volume of peat (white peat)

Test vessel: plastic pots of 1.5 liter capacity

A base fertiliser was first added to each pot, and in particular 0.25 gof phosphorus pentoxide in the form of superphosphate and 0.40 g ofpotassium oxide in the form of potassium magnesia were added per literof soil.

The particular amount desired of the test preparation was then placed onthe surface of the soil.

Evaluation was carried out after 3 months. The average growth height andthe appearance of the plants were evaluated in each case. The ratingshad the following meanings:

1=very dark to dark green

3=medium green

5=light green

0=yellow to chlorotic

The active compound preparations, amounts applied and test results canbe seen from the table which follows.

                  TABLE E                                                         ______________________________________                                        Fertilisation test/test in the open                                                                          Characteristic                                          g of N                rating of the green                                     per l of Average growth                                                                             coloration of the                              Preparation                                                                            soil     heigth in cm leaves                                         ______________________________________                                        (without --       18           7                                              fertiliser)                                                                   A        0.5      18           2                                                       1        19           2                                                       2.5      20           1                                              B        0.5      19           3                                                       1        22           2                                                       2.5      23           2                                              C        0.5      25           3                                                       1        26           2                                                       2.5      30           2                                              ______________________________________                                    

EXAMPLE F Fertilisation test/test in a greenhouse

Test plants: Chrysanthemum indicum; Variety: Yellow Delaware

Type of soil: sandy loam soil

Vessel: flowerpots containing 900 g of soil

Soil moisture during growing: about 70% of the maximum capacity forwater at 20° C.

The particular amount desired of the test preparation was placed on thesoil surface. Evaluation was carried out at various intervals of time.The average weight of fresh substance and the growth height of theplants was determined in each case.

The active compound preparations, amounts applied and test results canbe seen from the table which follows.

                  TABLE F                                                         ______________________________________                                        Fertilisation test/test in a greenhouse                                                                    Average weight                                                Average growth height per plant                                                               of fresh                                                mg of in cm after     substance per                                             N per   7       10    3     plant, in g,                             Preparation                                                                            vessel  weeks   weeks months                                                                              after 4 months                           ______________________________________                                        without a                                                                               0      15.3    18.5  24.3  11.0                                     preparation                                                                   ( = control)                                                                  D        150     25.0    32.0  47.0  17.5                                              375     22.5    33.5  53.0  18.3                                              750     22.0    30.0  53.5  16.8                                     G        150     23.3    32.5  47.8  19.3                                              375     24.0    32.8  53.3  19.0                                              750     17.3    26.0  45.5  12.0                                     E        150     24.0    30.8  48.2  17.0                                              375     24.0    34.5  57.2  21.8                                              750     17.3    23.8  46.0  15.5                                     F        150     24.3    31.8  49.3  17.5                                              375     25.3    35.5  58.8  22.8                                              750     15.3    23.3  47.0  18.0                                     ______________________________________                                    

EXAMPLE G Fertilisation test/test in a greenhouse

Test plant: common ryegrass (Lolium perenne), 1.8 per vessel

Type of soil: neutral sandy loam soil with 30% by volume of admixed peatfertiliser.

Vessel: plastic buckets, 5 kg of soil per vessel.

Soil moisture during growing: about 70% of the maximum capacity forwater at 20° C.

A base fertiliser was first added to each vessel, and in particular 0.9g of phosphorus pentoxide in the form of Thomas phosphate and 1.5 g ofpotassium oxide in the form of potassium magnesia were added per literof soil.

The particular amount desired of the test preparation was then placed onthe surface of the soil. Evaluation was carried out at various intervalsof time. The average fresh weight of grass cut was determined in eachcase.

The active compound preparations, amounts applied and test results canbe seen from the table which follows.

                                      TABLE G                                     __________________________________________________________________________    Fertilisation test/test in a greenhouse                                              g of                                                                              Average fresh weight per vessel, in g, after                              N per                                                                             1st cut                                                                            2nd cut                                                                             3rd cut                                                                             4th cut                                                                             5th cut                                                                             6th cut                                                                             Sum of                          Preparation                                                                          vessel                                                                            3 weeks                                                                            2 months                                                                            4 months                                                                            6 months                                                                            7 months                                                                            8 months                                                                            all cuts                        __________________________________________________________________________    without                                                                              0   2.5  7.0   5.3   2.0    1,4  1.1   41.8                            preparation                                                                   ( = control)                                                                  G      1   42.4 32.5  9.1   16.9  18,9  5.1   124.9                                  1.5 44.4 28.8  10.7  14.3  23,4  22.4  144.0                           E      1   40,1 25,9   8,8  10,9   8,9   3,4   98,0                                  1,5 42,7 25,4  10,2   4,4  16,2  12,8  111,7                           __________________________________________________________________________

PREPARATIVE EXAMPLES EXAMPLE 1

Comparison experiment: polymerisation of monomeric hydrocyanic acid inthe presence of potassium cyanate (see Angew. Chem. 72, (1960) page 380,Example 4)

200 parts by weight of a 30% strength aqueous hydrocyanic acid solutionwere warmed to 40° to 50° C. in the presence of 1.08 parts by weight ofpotassium cyanate for 5 hours. The product formed was filtered off,washed successively with distilled water and ethanol and then dried at80° C. Azulmic acid was obtained in the form of a black powder in ayield of 95% of theory.

Elementary analysis: 41.4% C; 4.0% H; 43.2% N; 11.4% O.

On the basis of the oxygen values given, this azulmic acid, the formulaof which is approximately characterised by the formula (I) indicatedearlier in this specification, had the empirical formula C₂₄ H₂₈ O₅ N₂₂(see Angew. Chem. 72 (1960) page 383).

Small amounts of monomeric hydrocyanic acid were continuously split offfrom this polymer, even after careful drying for a long time at roomtemperature or at 80° C. Subsequent intensive washing and reneweddrying, even under a high vacuum, did not stop the splitting back intohydrocyanic acid.

The determination of hydrogen cyanide was carried out by customarymethods.

When 2,000 g of the azulmic acid which had been prepared by the methodindicated above were stored at 50° C. in a container with a volume ofair of 12 liters, after 2 hours a hydrogen cyanide concentration of0.066 g of hydrogen cyanide per 12 liters of air was measured. Ahydrogen cyanide MWC (MWC=maximum workplace concentration) of 4,583 ppmwas calculated from this, that is to say a MWC value which was 416 timesgreater than the legally imposed MWC value of 11 ppm. An azulmic acid ofthis type is accordingly completely unsuitable for use in practice.

When 10 parts by weight of the azulmic acid prepared by the processdescribed above were treated with 100 parts by weight of distilled waterat 100° C. for 3 hours and the concentration of cyanide ions in thefiltrate was then determined, a concentration of cyanide ions was foundwhich corresponded to a hydrocyanic acid content of from 26 to over 28mg per liter of water. Such concentrations of cyanide ions causedestruction and deactivation of important bacteria, and their enzymesystems, occurring in soil.

EXAMPLE 2

Comparison experiment: polymerisation of monomeric hydrocyanic acid bythe "running in" process in the presence of ammonia (see German PatentSpecification No. 949,060).

A mixture of 5,600 g of water, 1,400 g of hydrocyanic acid and 88 g ofammonia was polymerised precisely according to the statements containedin Example 1 of German Patent Specification No. 949,060. After apolymerisation time of about 5 hours at 50° C. and after discontinuingthe cooling, the internal temperature rose to 90° C., remained at thislevel for about one hour and then fell. The azulmic acid formed wasisolated, washed with water and dried at 80° C. Yield: 98% of theory.

Stability to heat:

Storage of 2,000 g of the azulmic acid at 50° C. for two hours (seeExample 1): MWC value over 5,000 ppm.

Stability to hydrolysis:

Treatment of 10 parts by weight of the azulmic acid with 100 parts byweight of distilled water at 100° C. for three hours (see Example 1):hydrocyanic acid concentration of 30 to 36 mg per liter of water.

EXAMPLE 3

Comparison experiment: treatment of azulmic acid according to Example 1with ketones in the absence of water.

In each case 108 g of the azulmic acid prepared according to Example 1(disregarding the end groups, this amount corresponded on average to 2base mols of polymerised aminocyanocarbene units having the structure##STR52## were treated with 4 moles of one of the anhydrous ketonesmentioned below and with 4 moles of xylene, which acted as an entrainingagent for water, in each case for 30 hours at 120° C.: (a)cyclohexanone, (b) methyl ethyl ketone, (c) diethyl ketone and (d)methyl isobutyl ketone.

Besides small amounts of hydrocyanic acid being split off (about 0.5percent by weight), in all cases no formation of polyketimine,associated with the splitting off of water, took place between theketones and the amino groups of the azulmic acid. Small amounts ofhydrocyanic acid were trapped as cyanohydrins. After the treatment hadended, in each case about 107 g of azulmic acid were isolated, which,according to elementary analysis, was of virtually unchangedcomposition. These azulmic acid products treated with ketones were notstabilised; small amounts of hydrocyanic acid were split off at roomtemperature and also at 50° C. Even boiling the azulmic acid withacetone for several hours with continuous removal of the acetone did notlead to polyketimines or to substituted crosslinked condensationproducts containing aminal groups.

EXAMPLE 4

108 g (=2 base mols) of the azulmic acid prepared by the methoddescribed in Example 1 were stirred into 1,000 g (=10 mols) of 30%strength aqueous formalin solution and the mixture was kept at 100° C.for 8 hours. Although the azulmic acid was completely insoluble in thereaction medium, on tiltration of filtered samples, which were removedfrom the reaction medium at intervals of one hour in each case, acontinuous decrease in formaldehyde was found. A total of about 1.8 molsof formaldehyde was consumed per 2 base mols of aminocyanocarbene units.This corresponded to an amount of about 0.9 mol of formaldehyde per molof amino groups, which meant that in spite of the topochemical,heterogeneous reaction, almost every amino group in the azulmic acidunderwent reaction. The mixture was worked up by a procedure in whichthe reaction product was filtered off, washed with water and then freedfrom moisture and traces of formaldehyde with methanol.

Elementary analysis: 44.1% C; 4.4% H; 30.5% N; 21.4% O.

The reaction product was extremely stable towards the splitting off ofhydrogen cyanide under the influence of heat. As hydrogen cyanidedeterminations showed, both at room temperature and at 50° C., onlytraces of hydrogen cyanide were split off. Hydrocyanic acid could not bedetected even at 160° C.

The hydrolysis test described in Example 1 was likewise negative in thiscase.

Even in the mother liquor of the reaction product, neither monomerichydrocyanic acid itself nor its reaction product with formaldehyde, thatis to say hydroxyacetonitrile, could be detected.

At 100° C. and under the most diverse conditions, the azulmic acidstabilised with formaldehyde in each case had a value of hydrogencyanide split off of 0 ppm.

Whilst the azulmic acids prepared according to Example 1 dissolved in 1N aqueous sodium hydroxide solution even in the cold, hydrogen cyanidebeing split off and a deep black-coloured solution being obtained, theazulmic acid stabilised by reaction with formaldehye was completelystable and insoluble in 1 N aqueous sodium hydroxide solution.

EXAMPLE 5

108 g (=2 base mols) of the azulmic acid prepared according to Example 1were stirred into a mixture of 970 ml of water and 25 g of a 30%strength formalin solution (=0.25 mol of formaldehyde) and the mixturewas kept at 100° C. for 8 hours. Although only some of the amino groupsof the azulmic acid reacted with formaldehyde (aminal formation,methylolation and a crosslinking reaction), after the reaction hadended, a solid product was isolated which was completely resistanttowards splitting back into hydrogen cyanide at room temperature. Nohydrogen cyanide could be detected even at 50° C. A MWC value of zerothus resulted for the reaction product.

EXAMPLE 6

In each case 100 g of the stabilised azulmic acids prepared according toExample 4 and 5 were stirred at room temperature for 2 hours with (a)0.33 mol of phosphoric acid or (b) 0.48 mol of nitric acid. The mixtureswere then worked up by a procedure in which the black solid productpresent in each case was filtered off and dried. In this manner,phosphoric acid addition salts and nitric acid addition salts of theazulmic acids, stabilised with formaldehyde, employed were obtained,that is to say compounds in which the particular acid was bonded to thepolymer matrix via the amino groups which were still free (=anchorgroups) in the stabilised azulmic acids.

EXAMPLE 7

(a) 1,000 g of distilled water and 98 g (1 mol) of phosphoric acid wereadded to 108 g (2 base mols) of an azulmic acid prepared according toExample 2, after prior drying of the acid, at 80° C. in a closed stirredapparatus and the mixture was heated to 100° C. The reaction mixture waskept at this temperature for 16 hours, and during this time, in whichheterogeneous hydrolysis or partial decyclisation took place in theazulmic acid, a stream of nitrogen, serving as a propellant gas, waspassed through the reaction mixture at a rate of about 50 ml per minute.The stream of nitrogen issuing from the mixture was passed through twowash bottles connected in series, the first being filled with 200 ml of1 N aqueous hydrochloric acid in order to bond the ammonia contained inthe stream of nitrogen and the second wash bottle being charged with 200ml of 1 N aqueous sodium hydroxide solution in order to bond the carbondioxide present in the stream of nitrogen. The amounts of ammonia andcarbon dioxide evolved from the azulmic acid were determinedtitrimetrically at intervals of 1 to 3 hours. After a reaction time of16 hours, the total amount of ammonia which was formed by hydrolyticproduction of F₁ structural defects of the formula ##STR53## was 6.4 g(ca. 0.38 mol). The total amount of carbon dioxide which was formed bydecarboxylation of F₁ structural defects to give F₂ structural defectsof the formula ##STR54## was 4.3 g (ca. 0.1 mol) (determinedtitrimetrically by the barium carbonate method). A round molar NH₃ /CO₂quotient of about 3.8 was calculated from these figures. This numericalvalue indicated that of about 4 carboxyl groups (F₁ structural defects)produced by decyclisation and saponification of nitrile groups of theazulmic acid, about one was decarboxylated and thus led to an F₂structural defect.

The mixture was worked up by a procedure in which the solid reactionproduct was filtered off, washed and dried. 109 g of a (modified)azulmic acid containing F₁ structural defects and F₂ structural defectswere obtained.

On the basis of this yield information and of the molar NH₃ /CO₂quotient determined of 3.8, and on the basis of the fact that the F₂structural defects are formed from the F₁ structural defects (0.38mol-0.1 mol=0.28 mol), it could be calculated that 100 parts by weightof the process product contained about 18.6 percent by weight of F₁structural defects and about 2.67 percent by weight of F₂ structuraldefects. The sum of F₁ structural defects and F₂ structural defects was21.3 percent by weight.

As the elementary analysis showed, the modified azulmic acid containsabout 9.3 percent by weight of phosphoric acid. This phosphoric acid wasbonded to the polymer matrix via the free amino groups (anchor groups)of the modified azulmic acid.

(b) A mixture of 100 g of the modified azulmic acid prepared by themethod described under (a), 2 moles of formaldehyde and 600 ml of waterwas heated to 100° C. for 6 hours. Thereafter, the mixture was worked upby a procedure in which the solid product was filtered off, washed anddried. In this manner, 118 g of an azulmic acid containing F₁ structuraldefects and F₂ structural defects, which was stabilised withformaldehyde and was extremely stable towards the splitting off ofhydrogen cyanide under the influence of heat and under hydrolysisconditions, were obtained. The value for the splitting off of hydrogencyanide was virtually 0 ppm, even when it was measured under veryunfavourable conditions (small volume of air).

As was found in a determination of NH₂ groups by the method of van Slyke(see Angew. Chem. 72 (1960), page 382), the modified azulmic acid usedas the starting material in the above reaction contained about 21percent by weight of reactive NH₂ groups (=about 1.25 NH₂ equivalents)per 100 parts by weight. Accordingly, about 37.5 parts by weight offormaldehyde (=about 1.25 equivalents) should be consumed in theazomethine formation (--N═CH₂) and the crosslinking of the azomethinegroups by polymerisation. Balancing of the formaldehyde analytically bythe peroxide method of Blank and Finkenbeiner (compare Gattermann "DiePraxis des organischen Chemikers," De Gruyter & Co., Berlin 1962, page180; and Berichte 31, 2979 (1898) showed, however, that only about 0.8mol of formaldehyde had reacted. Thus, in the stabilized azulmic acidprepared according to the above process from a modified azulmic acid andformaldehyde, either 0.45 equivalent of free amino groups were stillpresent, or this 0.45 equivalent of amino groups had reactedintermolecularly or intramolecularly, with aminal formation, accordingto the equation which follows. ##STR55##

In the latter case, a quantitative condensation of all the amino groupswould have been achieved. According to the present state of theanalytical methods, it could not be decided which proportion of aminogroups had reacted with formaldehyde in the equivalence ratio 1:1 andwhich proportion of amino groups had been reacted with formaldehyde inthe equivalence ratio 2:1.

EXAMPLE 8

In each case 100 g of an azulmic acid, prepared according to Example7(b), stabilised with formaldehyde were dispersed in 250 g of water andthe dispersions were stirred with (a) 10.78 g (=0.11 mol) of phosphoricacid or (b) 30.2 g (=0.48 mol) of nitric acid at room temperature for 2hours. Phosphoric acid salts and nitric acid salts of the azulmic acid,stabilised with formaldehyde, employed were obtained in this manner. Inthis procedure, the inorganic acids were fixed to the polymer matrix viathe amino groups which were still free and/or via aminal groups of theformula <N--CH₂ --N>.

EXAMPLE 9

(a) 1,000 g of distilled water and 0.5 mol of calcium sulphite dihydratewere added to 108 g (2 base mols) of an azulmic acid prepared accordingto Example 2, after prior drying of the acid, at 80° C. in a closedstirred apparatus and the mixture was heated to 100° C. The reactionmixture was kept at this temperature for 8 hours and, during this time,a stream of nitrogen was passed through at a rate of about 50 ml perminute. The content of ammonia and carbon dioxide in the stream ofnitrogen issuing from the reaction mixture was determined in the mannerindicated in Example 7. A modified azulmic acid was obtained, the molarNH₃ /CO₂ quotient of which was 2.68.

(b) A mixture of 100 g of the modified azulmic acid prepared by themethod described under (a), 20 g of a 30% strength aqueous formalinsolution (=0.2 mol of formaldehyde) and 400 g of water was heated to100° C. for 8 hours. The mixture was then worked up by a procedure inwhich the solid product was filtered off, washed and dried. In thismanner, an azulmic acid containing F₁ structural defects and F₂structural defects and stabilised with formaldehyde was obtained, fromwhich, after prior drying at 30°-50° C., no hydrogen cyanide was splitoff on subsequent storage at room temperature. The reaction product wassoluble in 1 N aqueous sodium hydroxide solution.

EXAMPLE 10

In each case 100 g of the stabilised azulmic acid prepared according toExample 9(b) were stirred at room temperature for 2 hours with (a) anexcess of 1 molar phosphoric acid or (b) an excess of 1 molar nitricacid. Thereafter, the solid product was filtered off and dried.Phosphoric acid salts and nitric acid salts of the azulmic acid,stabilised with formaldehyde, employed were obtained in this manner,0.12 mol of phosphoric acid or 0.51 mol of nitric acid being bonded to100 parts by weight of stable azulmic acid.

EXAMPLE 11

(a) 1,000 g of deionised water were added to 108 g (2 base mols) of anazulmic acid prepared according to Example 2, after prior drying of theacid, at 80° C. in a closed stirred apparatus and the mixture was heatedto 100° C. The reaction mixture, in which the pH value was 6.2, was keptat this temperature for 8 hours, and during this time a stream ofnitrogen was passed through at a rate of 50 ml per minute. The contentof ammonia and carbon dioxide in the stream of nitrogen issuing from thereaction mixture was determined in the manner indicated in Example 7.The total amount of ammonia evolved was 0.059 mol.

The total amount of carbon dioxide evolved was 0.023 mol.

This gave a molar NH₃ /CO₂ quotient of 2.57.

By obtaining the difference between the amounts of ammonia and carbondioxide evolved (0.059-0.023=0.036), it was calculated that about 0.036equivalent of F₁ structural defects was formed and about 0.023equivalent of F₂ structural defects was formed.

Yield of modified azulmic acid: 107 g.

From this yield information, the molar NH₃ /CO₂ quotient and thedifference between the molar amounts of ammonia and carbon dioxideevolved (0.059-0.023=0.036), it was calculated that 100 parts by weightthe process product contain about 2.57 percent by weight of F₁structural defects and about 0.7 percent by weight of F₂ structuraldefects.

(b) A mixture of 100 g of the modified azulmic acid prepared by themethod described under (a), 20 g of a 30% strength aqueous formalinsolution (=0.2 mol of formaldehyde) and 400 g of water was heated to100° C. for 8 hours. The mixture was then worked up by a procedure inwhich the solid product was filtered off, washed and dried. In thismanner, an azulmic acid containing F₁ structural defects and F₂structural defects and stabilised with formaldehyde, was obtained, fromwhich, after prior drying at 30°-50° C., no hydrogen cyanide was splitoff on subsequent storage at room temperature. The reaction product wassoluble in 1 N aqueous sodium hydroxide solution.

EXAMPLE 12

In each case 100 g of the stabilised azulmic acid prepared according toExample 11(b) were stirred with (a) an excess of 1 molar phosphoric acidor (b) an excess of 1 molar nitric acid at room temperature for 2 hours.Thereafter, the solid product was filtered off and dried. Phosphoricacid salts and nitric acid salts of the azulmic acid, stabilised withformaldehyde, employed were obtained in this manner, 0.16 mol ofphosphoric acid or 0.54 mol of nitric acid being bonded to 100 parts byweight of stabilised azulmic acid.

EXAMPLE 13

(a) 350 g of approximately 25 percent strength by weight aqueous ammoniasolution (=87.5 g (about 5.15 mols) of ammonia) which contained 70 g(1.1 mols) of sodium cyanate, were added to 7 liters of 20% strengthaqueous hydrocyanic acid (=1,400 g (52 mols) of hydrogen cyanide),whilst stirring intensively. This mixture was warmed to 40° C.Thereafter, the temperature rose to 70° C. due to the heat ofpolymerisation liberated. The mixture was heated to 90° C. for a further4 hours and then worked up by a procedure in which the brown-blackpolymer obtained, which formed no colloidal solutions in water, wasfiltered off, washed successively with water and ethanol and then driedat 50°-80° C. under reduced pressure.

Yield: 94.9% of theory.

Elementary analysis: 40.6% C; 4.1% H; 42.4% N; 12.8% O.

The concentration of carbonate detected in the mother liquor of thepolymerisation mixture corresponded to an amount of carbon dioxideevolved of about 0.02 mol per 100 g of polymer. Accordingly, 0.56percent by weight of F₂ structural defects had already been introducedinto the product during the preparation of the polymer. Furthermore, onthe basis of a molar NH₃ /CO₂ quotient of about 4, such as had beenfound for hydrolysis of sodium cyanate-free azulmic acid at 90° C. fortwo hours in a parallel experiment, an amount of ammonia of 0.08 mol hadbeen evolved per 100 g of the polymer prepared, which corresponded to acontent of F₁ structural defects of 4 percent by weight.

Thus, the polymer prepared in the above process was an azulmic acidcontaining F₁ structural defects and F₂ structural defects, that is tosay a modified azulmic acid.

(b) When 100 g of the modified azulmic acid prepared by the methoddescribed under (a) were reacted with 0.2 mol of formaldehyde under theconditions indicated in Example 7(b), an azulmic acid containingstructural defects and stabilised with formaldehyde was formed, fromwhich no hydrogen cyanide was split off at room temperature. Thedetection of hydrogen cyanide carried out with small Drager tubes wasnegative (0 ppm of hydrogen cyanide).

EXAMPLE 14

When 100 g of the modified azulmic acid prepared according to Example13(a), were reacted with 0.2 mol of glyoxal under the conditionsindicated in Example 7(b), an azulmic acid containing structural defectsand stabilised with glyoxal was formed, from which no hydrogen cyanidewas split off at room temperature. A hydrogen cyanide detection whichwas carried out, using a small Drager tube, in the volume of air over asample of the process product stored at room temperature was negative.

EXAMPLE 15

108 g of the modified azulmic acid prepared according to Example 13(a)were stirred into 1,000 g (=10 mols) of 30% strength aqueous formalinsolution and the mixture was kept at 100° C. for 8 hours. The mixturewas then worked up by a procedure in which the reaction product wasfiltered off, washed with water and then freed from moisture and tracesof formaldehyde with methanol. 150 g of stabilised azulmic acid wereobtained, from which no hydrogen cyanide was split off even at 180° C.In the case of a sample stored at 60° C., a value for the splitting offof hydrogen cyanide of 0 ppm was measured.

EXAMPLE 16

(a) 4 liters of 20% strength aqueous hydrocyanic acid, 200 ml ofapproximately 25% strength aqueous ammonia solution and 40 g of sodiumcyanate were stirred together. This reaction mixture was heated to 90°C. in the course of 2 hours. Thereafter, the mixture was stirred at 90°C. for a further 30 minutes, using a very effective reflux condenser andutilising the hydrocyanic acid reflux, 500 ml of water and a smallamount of hydrocyanic acid were then distilled off and 500 ml of waterwere again added. The mixture was then stirred at 100° C. for 5 hours.The black process product thereby obtained, which could be filteredexcellently, was filtered off, washed successively with about 4 litersof water and with methanol and dried under reduced pressure.

Yield: 845 g of azulmic acid containing F₁ structural defects and F₂structural defects.

Content of structural defects: about 11 percent by weight.

Elementary analysis: 38.2% C; 4.9% H; 38.8% N; 18.9% O.

As can be seen from these values, the product had a higher oxygencontent and a lower nitrogen content than the azulmic acid preparedaccording to Example 1. This indicated that the product contains a largeproportion of structural defects (F₁ and F₂).

(b) 108 g of the modified azulmic acid prepared by the method describedunder (a) were stirred into 1,000 g (=10 mols) of 30% strength aqueousformalin solution and the mixture was kept at 100° C. for 8 hours. Themixture was then worked up by a procedure in which the reaction productwas filtered off, washed with water and then freed from moisture andtraces of formaldehyde with methanol. 140 g of stabilised azulmic acidwere obtained, from which no hydrogen cyanide was split off even at 200°C. (test for hydrogen cyanide using a small Drager tube).

Elementary analysis: 45.1% C; 5.1% H; 31.3% N; 18.6% 0.

EXAMPLE 17

(a) When the hydrocyanic acid polymerisation described in Example 16(a)was carried out with the aid of aqueous ammonia solution and sodiumcyanate, as the catalyst, at 40° C. under the conditions indicated inExample 1, an azulmic acid was obtained which was virtually free fromstructural defects and thus had a relatively low oxygen content.

Elementary analysis: 41.6% C; 3.9% H; 45.8% N; 7.5% O.

(b) 108 g of the azulmic acid prepared by the method described under (a)were stirred into 1,000 g (=10 mols) of 30% strength aqueous formalinsolution and the mixture was kept at 100° C. for 8 hours. The mixturewas then worked up by a procedure in which the reaction product wasfiltered off, washed with water and then freed from moisture and tracesof formaldehyde with methanol. 145 g of stabilised azulmic acid wereobtained, from which no hydrogen cyanide was split off even at 200° C.(test for hydrogen cyanide using a small Drager tube).

Elementary analysis: 45.9% C; 4.9% H; 32.6% N; 16.8% O.

As can be seen from these values, this stabilised azulmic acid alsocontained structural defects. The latter had thus been introduced in thecourse of the reaction of the azulmic acid virtually free fromstructural defects, which is used as the starting material, withformaldehyde.

EXAMPLE 18

A mixture of 108 g of the modified azulmic acid prepared according toExample 16(a) (content of structural defects about 11 percent byweight), 0.5 mol of imidazole and 800 ml of water was warmed to 100° C.for 20 hours. The mixture was then worked up by a procedure in which thesolid product was filtered off, washed and dried. A modified azulmicacid was obtained which, on the basis of the balance determined for thesplitting off of ammonia and carbon dioxide, contained about 30 percentby weight of F₁ structural defects.

When this azulmic acid containing a high proportion of structuraldefects was reacted with formaldehyde under the conditions indicated inExample 4, a stabilised azulmic acid was obtained, from which nohydrogen cyanide was split off, even on prolonged storage at 50° C.

EXAMPLE 19

(a) A mixture of 200 g of the azulmic acid prepared according to Example13(a), with a relatively low content of structural defects (composition:40.6% C; 4.1% H; 42.4% N; 12.8% O) and 800 g of a 25% strength aqueousammonia solution was stirred at 25°-31° C. for 8 hours. The black powderwas then filtered off, washed with 5 liters of water and dried at roomtemperature in a vacuum drying cabinet. Yield: 215 g of a modifiedazulmic acid which contained about 6-7 percent by weight of ammoniabonded to F₁ structural defects. The formula of modified F₁ structuraldefects of this type could be illustrated as follows: ##STR56##

Elementary analysis: 37.6% C; 4.8% H; 38.5% N; 19.4% O.

When the process product was dried not at room temperature but at highertemperatures, ammonia was readily split off.

(b) By reacting 100 g of the modified azulmic acid containing ammonia,prepared by the method described under (a), with 0.2 mol of formaldehydeat 50° C. in an aqueous solution, a product was obtained which did nottend to split off hydrogen cyanide at temperatures up to 30° C.

A stream of nitrogen was passed over some of this process product at 50°C. for four hours at a flow rate of 100 ml of nitrogen per minute. Nohydrogen cyanide could be detected analytically in the gas collected(hydrogen cyanide concentration=0 ppm).

Ammonia was readily split off from the process product both underhydrolysis conditions and under the influence of heat. At 50° C., aproportion of ammonia of 1.43 percent by weight was liberated in thecourse of one hour.

When the process product which smelled slightly of ammonia, was gassedin the moist state with carbon dioxide, a virtually odourless powder wasobtained.

(c) Some of the product prepared according to (b) was washed thoroughlywith water and once again treated with 25% strength aqueous ammoniasolution for renewed production of structural defects. The productthereby formed exhibited no tendency to split off hydrogen cyanide evenat 50° C.

EXAMPLE 20

(a) A mixture of 200 g of the azulmic acid prepared according to Example13(a), with a relatively low content of structural defects, and 800 g ofa 25% strength aqueous ammonia solution was stirred at 80° C. in aclosed apparatus for 3 hours. The black powder was then filtered off,washed with 5 liters of water and dried at room temperature in a vacuumdrying cabinet. A modified azulmic acid was obtained which containedabout 13 percent by weight of ammonia bonded to F₁ structural defects.

(b) By reacting 100 g of the modified azulmic acid containing ammonia,prepared by the method described under (a) with 0.2 mol of formaldehydeat 50° C. in an aqueous solution, a product was obtained which did nottend to split off hydrogen cyanide at temperatures up to 60° C.

Ammonia was readily split off from the process product both underhydrolysis conditions and under the influence of heat.

(c) Some of the product prepared according to (b) was washed thoroughlywith water and once again treated with 25% strength aqueous ammoniasolution for renewed production of structural defects. The productthereby formed exhibited no tendency to split off hydrogen cyanide evenat 70° C.

EXAMPLE 21

(a) A mixture of 108 g of the azulmic acid prepared according to Example13(a), 14 g of calcium thiosulphate hexahydrate and 800 ml of water waswarmed to 100° C. for 1.6 hours. The mixture was then worked up by aprocedure in which the solid product was filtered off, washed and dried.A modified azulmic acid was obtained which, on the basis of the amountsof ammonia and carbon dioxide evolved, contained about 3.3 percent byweight of F₁ structural defects additionally formed and about 1.4percent by weight of F₂ structural defects additionally formed.

(b) By reacting 100 g of the modified azulmic acid prepared according to(a) with 0.2 mol of formaldehyde at 50° C. in an aqueous solution, aproduct was obtained from which no hydrogen cyanide was split off evenon storage at 30° C. for several months. A hydrogen cyanideconcentration of 0 ppm was measured in the volume of air in a vesselwhich was half-filled with the process product.

EXAMPLE 22

(a) A mixture of 108 g of the modified azulmic acid prepared accordingto Example 13(a), 19 g of calcium dihydrogen sulphide hexahydrate and800 ml of water was warmed to 100° C. for 2 hours. The mixture was thenworked up by a procedure in which the solid product was filtered off,washed and dried. A modified azulmic acid was obtained which containedabout 2 percent by weight of calcium and, as was given by the amounts ofammonia and carbon dioxide evolved, had an approximate content of F₁structural defects additionally formed of 7 percent by weight and of F₂structural defects additionally formed of 0.9 percent by weight.

(b) By reacting 100 g of the modified azulmic acid prepared according to(a) with 0.2 mol of formaldehyde at 50° C. in an aqueous solution, aproduct was obtained from which no hydrogen cyanide was split off evenon storage at 30° C. for several months. A hydrogen cyanideconcentration of 0 ppm was measured in the volume of air in a vesselwhich was half-filled with the process product.

EXAMPLE 23

(a) A mixture of 108 g of the modified azulmic acid prepared accordingto Example 13(a) and 1,000 ml of a 1 N aqueous potassium hydroxidesolution was warmed to 100° C. for 44 hours. The azulmic acid employedwas thereby already completely dissolved a few minutes after the startof the reaction.

The progress of the saponification reaction was monitored by measuringthe amounts of ammonia and carbon dioxide evolved. The amount of ammonialiberated was 12.2 g after 8 hours, 15 g after 22 hours and 17 g (=1mol) after 44 hours.

In a parallel experiment carried out under exactly the same conditions,it was found that by acidifying the reaction mixture with 2 mols ofaqueous hydrochloric acid, about 21.9 g (=0.5 mol) of carbon dioxidewere bonded in the solution as potassium carbonate.

The mixture was worked up by a procedure in which the brown-blackaqueous reaction solution was concentrated under 14 mm Hg, methanol wasadded three times, in an amount of 1 liter each time, to the brown-blackdispersion thereby formed and each time the mixture was concentrated bydistilling off the methanol and the water still present, and thecrystals which remained were then boiled up briefly once again with 800ml of methanol and filtered off. 113 g of a water-soluble product with ahumus-like colour were obtained.

Elementary analysis: 31.5% C; 3.9% H; 26.8% N; 21.0% O; 16.1% K.

The amounts measured of ammonia and carbon dioxide liberated gave amolar NH₃ /CO₂ quotient of 2.

The difference between the numbers of mols of ammonia and carbon dioxidedetermined was about 0.5. This factor indicates that about half of allthe F₁ structural defects had been converted into F₂ structural defects.

On the basis of these figures, it was calculated that 100 parts byweight of the process product contained about 55 percent by weight ofpotassium salt F₁ structural defects of the formula ##STR57## and about14.5 percent by weight of F₂ structural defects. In this method forproducing structural defects, in each case one potassium salt F₁structural defect of the above formula was accordingly formed per 2cyclic units of the azulmic acid. In the ideal case, a product of thistype can be illustrated by the formula which follows: ##STR58##

If both the polymolecularity of the process product and the fact thatoxygen atoms in the form of carbonyl groups (which help to increase theoxygen content) were present in the "anionic" and "cationic" portion ofend groups in the azulmic acid, the values found in the elementaryanalysis were in relatively good agreement with those for products whichhave average molecular weights of between 600 and 800. By way ofcomparison, the elementary composition which follows was calculated fora single compound of the empirical formula C₂₁ H₂₈ N₁₇ O₉ K₃ (molecularweight=789): 32.4% C; 3.5% H, 30.5% N; 18.5% O; 15.1% K.

The process product, which could be described as a polyelectrolyte,contained a low-molecular fraction which was particularly readilysoluble in water and, on the basis of its elementary composition, couldbe illustrated approximately by the formula which follows: ##STR59##

(Molecular Weight 569).

Elementary analysis of the low-molecular product: 35.7% C; 2.5% H; 23.5%N; 23.7% O; 14.5% K.

(b) By reacting the azulmic acid potassium salt prepared by the methoddescribed under (a) with formaldehyde in an aqueous solution, an azulmicacid potassium salt/formaldehyde condensation product was formed whichwas stable towards the splitting off of hydrogen cyanide.

The salts, listed in Table 1 which follows, of modified azulmic acidswere also obtained by the method described in Example 23(a) by reactingazulmic acid prepared according to Example 13(a) with the correspondingbases or basic salts:

                  TABLE 1                                                         ______________________________________                                        Example Base or                                                               No.     salt      Product      Colour                                         ______________________________________                                        24(a)   K.sub.2 CO.sub.3                                                                        Azulmic acid                                                                  potassium salt                                                                             humus-coloured                                 25(a)   KHCO.sub.3                                                                              Azulmic acid                                                                  potassium salt                                                                             "                                              26(a)   Na.sub.2 S                                                                              Azulmic acid                                                                  sodium salt  "                                              27(a)   K.sub.2 S Azulmic acid                                                                  potassium salt                                                                             "                                              28(a)   Na.sub.2 S.sub.2 O.sub.3                                                                Azulmic acid                                                                  sodium salt  "                                              29(a)   LiOH      Azulmic acid                                                                  lithium salt "                                              ______________________________________                                    

The compounds listed in Table 2 which follows were obtained from theazulmic acid potassium salt, prepared according to Example 23(a), byreaction with metal halides, metal hydroxides, metal nitrates or metalsulphates in an aqueous solution.

                  TABLE 2                                                         ______________________________________                                        Example  Metal salt                                                           No.      or base     Product                                                  ______________________________________                                        30(a)    Ca(OH).sub.2                                                                              Azulmic acid calcium salt                                31(a)    Ba(OH).sub.2                                                                              Azulmic acid barium salt                                 32(a)    PbCL.sub.4  Azulmic acid lead salt                                   33(a)    MgCl.sub.2  Azulmic acid magnesium salt                              34(a)    SrCl.sub.2  Azulmic acid strontium salt                              35(a)    FeSO.sub.4  Azulmic acid iron salt                                   36(a)    CoSO.sub.4  Azulmic acid cobalt salt                                 37(a)    CuSO.sub.4  Azulmic acid copper salt                                 38(a)    MnSO.sub.4  Azulmic acid manganese salt                              39(a)    NiCl.sub.2  Azulmic acid nickel salt                                 40(a)    ZnSO.sub.4  Azulmic acid zinc salt                                   41(a)    SnCl.sub.4  Azulmic acid tin salt                                    42(a)    CdSO.sub.4  Azulmic acid cadmium salt                                43(a)    Bi.sub.2 (SO.sub.4).sub.3                                                                 Azulmic acid bismuth salt                                44(a)    Al.sub.2 (SO.sub.4).sub.3                                                                 Azulmic acid aluminium salt                              45(a)    AgNO.sub.3  Azulmic acid silver salt                                 46(a)    HgCl.sub.2  Azulmic acid mercury salt                                47(a)    AuCl.sub.3  Azulmic acid gold salt                                   ______________________________________                                    

The condensation products listed in Table 3 below were also obtained bythe method indicated in Example 23(b), from the corresponding salts ofazulmic acid and formaldehyde.

                  TABLE 3                                                         ______________________________________                                        Example                                                                       No.        Formaldehyde condensation product of:                              ______________________________________                                        26(b)      Azulmic acid sodium salt                                                                          (26a)                                          29(b)      Azulmic acid lithium salt                                                                         (29b)                                          30(b)      Azulmic acid calcium salt                                                                         (30b)                                          31(b)      Azulmic acid barium salt                                                                          (31a)                                          32(b)      Azulmic acid lead salt                                                                            (32a)                                          33(b)      Azulmic acid magnesium salt                                                                       (33a)                                          34(b)      Azulmic acid strontium salt                                                                       (34a)                                          35(b)      Azulmic acid iron salt                                                                            (35a)                                          36(b)      Azulmic acid cobalt salt                                                                          (36a)                                          37(b)      Azulmic acid copper salt                                                                          (37a)                                          38(b)      Azulmic acid manganese salt                                                                       (38a)                                          39(b)      Azulmic acid nickel salt                                                                          (39a)                                          40(b)      Azulmic acid zinc salt                                                                            (40a)                                          41(b)      Azulmic acid tin salt                                                                             (41a)                                          42(b)      Azulmic acid Cadmium salt                                                                         (42a)                                          43(b)      Azulmic acid bismuth salt                                                                         (43a)                                          44(b)      Azulmic acid aluminium salt                                                                       (44a)                                          45(b)      Azulmic acid silver salt                                                                          (45a)                                          46(b)      Azulmic acid mercury salt                                                                         (46a)                                          47(b)      Azulmic acid gold salt                                                                            (47a)                                          ______________________________________                                    

EXAMPLE 48

A mixture of 108 g (2 base mols) of the azulmic acid prepared accordingto Example 1, 4 mols of glyoxal, 1,000 g of distilled water and 100 g ofethanol was warmed to 100° C. for 16 hours, whilst stirring intensively.The mixture was then worked up by a procedure in which the solid productwas filtered off, washed and dried. 140 g of an azulmic acid/glyoxalcondensation product were obtained, from which no hydrogen cyanide wassplit off even on prolonged storage at temperatures between 20° and 40°C.

From the amount of carbon dioxide evolved during the reaction and on thebasis of a molar NH₃ /CO₂ quotient of 3.2, the process product containedbetween 4 and 6 percent by weight of F₁ structural defects and F₂structural defects. The above condensation reaction therefore proceededwith simultaneous production of structural defects.

The condensation products listed in Table 4 below were obtained by themethod described in Example 48, by reacting in each case 108 g of theazulmic acid prepared according to Example 1 with 4 mols of theappropriate aldehyde.

                  TABLE 4                                                         ______________________________________                                        Example                              Yield                                    No.    Aldehyde      Product         (in g)                                   ______________________________________                                        49     Acetaldehyde  Az/acetaldehyde                                                               condensation product                                                                          115                                      50     Propionaldehyde                                                                             Az/propionaldehyde                                                            condensation product                                                                          126                                      51     Isobutyraldehyde                                                                            Az/isobutyraldehyde                                                           condensation product                                                                          124                                      52     Hydroxypival- Az/hydroxypivalalde-                                            aldehyde      hyde condensation                                                             product         125                                      53     Acrolein      Az/acroleinaldehyde                                                           condensation product                                                                          143                                      54     Glucose       Az/glucose con-                                                               densation product                                                                             128                                      55     Salicylaldehyde                                                                             Az/salicylaldehyde                                                            condensation product                                                                          121                                      56     Furfurol      Az/furfurol con-                                                              densation product                                                                             125                                      57     ω-Hydroxy-                                                                            Az/ω-hydroxymethyl-                                       methyl-furfurol                                                                             furfurol condensation                                                         product         139                                      58     Chloral hydrate                                                                             Az/chloralhydrate                                                             condensation product                                                                          149                                      ______________________________________                                         "Az" in each case represents "azulmic acid".                             

EXAMPLE 59

A mixture of 108 g of the azulmic acid prepared according to Example13(a), 0.3 mol of formaldehyde, 600 g of distilled water and 100 g offinely powdered ash of tobacco leaves (composition of the ash,calculated relative to oxides of the elements: 29.1% of K₂ O; 3.2% ofNa₂ O; 36.0% of CaO; 7.4% of MgO; 1.9% of Fe₂ O₃ ; 4.7% of P₂ O₅ ; 3.1%of SO₃ ; 5.8% of SiO₂ and 6.7% of Cl₂) was warmed to 100° C. for 6hours, whilst stirring intensively. The mixture was then worked up by aprocedure in which the solid product was filtered off, washed and dried.195 g of an azulmic acid/formaldehyde condensation product whichcontained tobacco ash and had an excellent stability towards thesplitting off of hydrocyanic acid were obtained.

Measurement of the amounts of ammonia and carbon dioxide evolved duringthe reaction showed that the condensation reaction proceeded withsimultaneous production of structural defects.

The condensation products listed in Table 5 below were obtained by themethod described in Example 59, by reacting in each case 108 g of theazulmic acid prepared according to Example 13(a) with 0.3 mol offormaldehyde in the presence of additives.

                                      TABLE 5                                     __________________________________________________________________________                               Amount of                                                                     additive                                           Example                    employed                                                                            Yield                                        No.  Additive              [g]   (in g)                                       __________________________________________________________________________    60   Finely powdered ash of willow                                                                       100   198                                               wood                                                                     61   Ash residues of broom, beech                                                  and birch leaves in the ratio                                                 1:1:1 (dry weight)    100   196                                          62   Ash of spruce wood    100   199                                          63   Customary garden mould with a                                                 moisture content of about 40%                                                 by weight             424   377                                          64   Polymethyleneurea of the form-                                                ula                   100   205                                                ##STR60##                                                               65   Peat                  100   180                                          66   1:1 mixture of insoluble                                                      calcium cyanate and calcium                                                   cyanamide             100   185                                          67   Powdered, sparingly soluble                                                   isobutyraldehyde/urea con-                                                    densate (molar ratio 1:1)                                                                           100   197                                          68   Powdered, sparingly soluble                                                   isobutyraldehyde/urea con-                                                    densate (molar ratio 2:1)                                                                           100   193                                          69   Isobutyraldehyde/urea con-                                                    densate (molar ratio 1:2.5)                                                                         100   190                                          70   Powdered, sparingly soluble                                                   crotonaldehyde/urea con-                                                      densate (molar ratio 1:2)                                                                           100   189                                          71   Powdered, sparingly soluble                                                   crotonaldehyde/urea con-                                                      densate (molar ratio 1:1)                                                                           100   193                                          72   Powdered, sparingly soluble                                                   crotonaldehyde/urea con-                                                      densate, prepared from 1 mol                                                  of crotonaldehyde and 2 mols                                                  of urea, essentially con-                                                     sisting of            100   204                                                ##STR61##                                                               73   Ground basic slag     100   205                                          74   Phosphorite           100   203                                          75   Rhenania phosphate    100   198                                          76   Active charcoal powder                                                                              100   204                                          77   Hydrated alumina      100   207                                          78   Silicon dioxide       100   206                                          __________________________________________________________________________

EXAMPLE 79

(a) 34 g of approximately 25% strength aqueous ammonia solution, whichcontained 6.8 g of sodium cyanate, were added to 600 ml of 18% strengthaqueous hydrocyanic acid and 100 g of polymethyleneurea, whilst stirringintensively. After warming the mixture to 40° C., the temperature roseto 70° C. due to the heat of polymerisation liberated. The mixture washeated to 90° C. for a further 4 hours and then worked up by a procedurein which the polymer was filtered off, washed successively with waterand ethanol and then dried under reduced pressure.

Yield: 201 g of modified azulmic acid which contained polymethyleneurea.

Nitrogen content of the process product: 38.9%.

(b) A mixture of 200 g of the modified azulmic acid prepared accordingto (a), containing polymethyleneurea, 200 ml of a 30% strength aqueousformalin solution (=2 mols of formaldehyde) and 1,200 ml of distilledwater was heated to 100° C. for 3 hours. After working up, a pulverulentazulmic acid/polymethyleneurea/formaldehyde condensation product wasobtained which was completely stable towards the splitting off ofhydrogen cyanide. On prolonged storage, a hydrogen cyanide concentrationof 0 ppm was measured in vessels containing air. About 1.6 mols offormaldehyde had been taken up during the condensation reaction.

Modified azulmic acids containing the additives listed in Table 6 belowwere also prepared by the method described in Example 79(a). In eachcase 1 liter of 19.2% strength aqueous hydrocyanic acid was polymerisedin the presence of, in each case, 180 g of additive.

                  TABLE 6                                                         ______________________________________                                        Example             Yield         Nitrogen content                            No.    Additive     (in g)        of the product                              ______________________________________                                        80(a)  Active charcoal                                                                            342           22.9%                                       81(a)  Bleaching earth                                                                            340           22.7%                                       82(a)  Asbestos flour                                                                             354           20.1%                                       83(a)  Trilon B     170           41.8%                                       84(a)  Starch (insoluble)                                                                         342           22.4%                                       85(a)  Fly ash "M"  353      about                                                                              22%                                         86(a)  Peat (moist) 155           31.3%                                       ______________________________________                                    

The azulmic acid/additive/formaldehyde condensation products listed inTable 7 below were also prepared by the method described in Example79(b)

                  TABLE 7                                                         ______________________________________                                        Example                                                                       No.      Condensation product of                                              ______________________________________                                        80(b)    Az/active charcoal + formaldehyde                                                                    (80a)                                         81(b)    Az/bleaching earth + formaldehyde                                                                    (81a)                                         82(b)    Az/asbestos flour + formaldehyde                                                                     (82a)                                         83(b)    Az/Trilon B + formaldehyde                                                                           (83a)                                         84(b)    Az/starch (insoluble) + formaldehyde                                                                 (84a)                                         85(b)    Az/fly ash "M" + formaldehyde                                                                        (85a)                                         86(b)    Az/peat (moist) + formaldehyde                                                                       (86a)                                         ______________________________________                                         "Az" in each case represents "azulmic acid"-                             

EXAMPLE 87

100 g of the azulmic acid prepared according to Example 13(a) andstabilised by condensation with a little formaldehyde were stirred withan excess of aqueous nitric acid at room temperature for 10 minutes.Thereafter, the solid product was filtered off and washed with a littlewater. An azulmic acid-nitric acid adduct was obtained in which 0.51 molof nitric acid were bonded per 100 parts by weight of stabilised azulmicacid. Accordingly, in spite of a heterogeneous reaction of about 4 aminogroups which were present in about 216 parts by weight of the azulmicacid employed, on average one amino group within the polycyclic matrixwas converted into a grouping of the formula ##STR62##

Elementary analysis of the product isolated: 35.2% C; 4.3% H; 38.9% N;20.9% O.

The process product contained about 19.2% by weight of nitrate ions.

Since in the case of the preparation of azulmic acids of this type,containing nitrate ions, there is the danger than when the products arewashed with a large quantity of water some of the nitrate ions containedtherein dissociate off, it is appropriate to wash the product only witha little water and to gas the moist powder, which still containsportions of nitric acid which is not ionically bonded, with ammonia.Nitric acid which is not ionically bonded is converted into ammoniumnitrate by this measure.

EXAMPLE 88

100 g of the azulmic acid prepared according to Example 13(a) andstabilised by condensation with a little formaldehyde was stirred withan excess of 2 normal aqueous nitric acid at room temperature for 5minutes. Thereafter, the solid product was filtered off and washed witha little water. An azulmic acid-nitric acid adduct was obtained in which0.64 mol of nitric acid were bonded per 100 parts by weight ofstabilised azulmic acid. Accordingly, on average about 1.3 amino groupequivalents were used for salt formation with nitric acid per 4 aminogroup equivalents in 216 parts by weight of stabilised azulmic acid.

Further experiments showed that the proportion of nitric acid absorbedwas greater, the more finely divided (for example particle size <100μ)was the stabilised azulmic acid employed.

The adducts listed in Table 8 below were also obtained by the methoddescribed in Example 87, by reacting in each case 100 parts by weight ofan azulmic acid stabilised with a little formaldehyde with an excess ofthe particular acid.

                  TABLE 8                                                         ______________________________________                                                                    Amount of acid                                    Example                     bonded per 100 g                                  No.     Adduct of           of azulmic acid                                   ______________________________________                                        89      Az + oleic acid     0.33 mol                                          90      Az + ricinoleic acid                                                                              0.25 mol                                          91      Az + dibutylphosphoric acid                                                                       0.25 mol                                          92      Az + 2-ethylcaproic acid                                                                          0.35 mol                                          93      Az + acrylic acid   0.38 mol                                          94      Az + methacrylic acid                                                                             0.4   mol                                         95      Az + maleic acid    0.4   mol                                         96      Az + maleic acid oleyl alcohol                                                                    0.34 mol                                                  monoester                                                             ______________________________________                                         "Az" in each case represents "stabilised azulmic acid".                  

The compounds listed in Example 89-96 had a hydrophobic character.

EXAMPLE 97

100 g of azulmic acid stabilised with formaldehyde and with a content ofF₁ structural defects of about 2.6 percent by weight and a content of F₂structural defects of 0.6 percent by weight were stirred with 0.5 mol ofcadmium (II) chloride and 600 ml of distilled water at room temperaturefor 6 hours. Thereafter, the solid product was filtered off, washedthoroughly with water and dried at 100° C. A black finely powderedproduct with a cadmium content of 8.1 percent by weight was isolated.The process product was azulmic acid, stabilised with formaldehyde whichcontained cadmium (II) chloride bonded as a complex. The azulmic acidcomplex salt was completely stable towards the splitting off of hydrogencyanide.

The complex salts listed in Table 9 below were also obtained by themethod described in Example 97, by reacting in each case 100 g ofazulmic acid stabilised with formaldehyde with in each case 0.5 mol ofchloride or sulphate of the corresponding metal.

                  TABLE 9                                                         ______________________________________                                        Example            Metal content of the azulmic acid                          No.      Metal salt                                                                              complex                                                    ______________________________________                                        98       MnSO.sub.4                                                                              3.65% by weight                                            99       SnCl.sub.2                                                                              23.5% by weight                                            100      CuSO.sub.4                                                                              10.4% by weight                                            101      HgCl.sub.2                                                                              28.4% by weight                                            102      CoCl.sub.2                                                                               5.2% by weight                                            103      ZnCl.sub.2                                                                              10.4% by weight                                            104      FeSO.sub.4                                                                               6.9% by weight                                            105      PbCl.sub.2                                                                              25.8% by weight                                            106      Bi(NO.sub.3).sub.3                                                                        21% by weight                                            107      AgNO.sub.3                                                                              26.7% by weight                                            ______________________________________                                    

EXAMPLE 108

(a) A mixture of 108 g of azulmic acid which was almost free fromstructural defects, 1 mol of the azulmic acidcadmium chloride complexprepared according to Example 97 and 1,000 g of distilled water wasstirred at 70° C. for 8 hours. The solid product was then filtered off,washed and dried. An azulmic acid-cadmium chloride complex with arelatively high content of F₁ structural defects and F₂ structuraldefects was obtained. The content of F₁ structural defects was about10-12 percent by weight.

(b) 120 g of the azulmic acid-cadmium chloride complex containingstructural defects, prepared by the method described under (a), weretreated with 1 mol of formaldehyde in an aqueous medium at 50° C. for 6hours. Thereafter, the solid product was filtered off, washed and dried.An azulmic acid-cadmium chloride complex stabilised by formaldehyde wasobtained, from which no hydrogen cyanide was split off even at 180° C.The product had a cadmium content of 17.3 percent by weight.

(c) 120 g of the product prepared according to (b) were stirred with anexcess of 1 N aqueous sodium hydroxide solution at 25° C. for 2 hours.Thereafter, the solid product was filtered off, washed and dried. Anazulmic acid-cadmium hydroxide complex stabilised by formaldehyde wasobtained.

The azulmic acid complexes, containing structural defects, listed inTable 10 below were obtained in the manner indicated in Example 108under (a) by reacting azulmic acid which was relatively free fromstructural defects with the corresponding azulmic acid-metal saltcomplex.

                  TABLE 10                                                        ______________________________________                                                                      Content of                                      Example                       F.sub.1 structural                              No.      Azulmic acid-metal salt complex                                                                    defects [%]                                     ______________________________________                                        109(a)   Az-MnSO.sub.4 complex                                                                              9                                               110(a)   Az-SnCl.sub.2 complex                                                                              12                                              111(a)   Az-CuSO.sub.4 complex                                                                              8                                               112(a)   Az-HgCl.sub.2 complex                                                                              7                                               113(a)   Az-CoCl.sub.2 complex                                                                              10.5                                            114(a)   Az-ZnCl.sub.2 complex                                                                              13                                              115(a)   Az-FeSO.sub.4 complex                                                                              8                                               116(a)   Az-PbCl.sub.2 complex                                                                              9                                               117(a)   Az-Bi(NO.sub.3).sub.3 complex                                                                      8                                               118(a)   Az-AgNO.sub.3 complex                                                                              7                                               ______________________________________                                         "Az" in each case represents "azulmic acid".                             

The azulmic acid-metal salt complexes listed in Table 10 were subjectedto a condensation reaction with formaldehyde by the method indicated inExample 108 under (b). The azulmic acid-metal salt complexes, stabilisedwith formaldehyde, listed in Table 11 below were thereby obtained.

                  TABLE 11                                                        ______________________________________                                        Example                                                                       No.    Formaldehyde condensation product of:                                                                Metal content                                   ______________________________________                                        109(b) Az-MnSO.sub.4 complex according to                                                                   3.2% of Mn                                             Example 109(a)                                                         110(b) Az-SnCl.sub.2 complex according to                                                                   18% of Sn                                              Example 110(a)                                                         111(b) Az-CuSO.sub.4 complex according to                                                                   9.6% of Cu                                             Example 111(a)                                                         112(b) Az-HgCl.sub.2 complex according to                                                                   26% of Hg                                              Example 112(a)                                                         113(b) Az-CoCl.sub.2 complex according to                                                                   5.3% of Co                                             Example 113(a)                                                         114(b) Az-ZnCl.sub.2 complex according to                                                                   9.5% of Zn                                             Example 114(a)                                                         115(b) Az-FeSO.sub.4 complex according to                                                                   7.2% of Fe                                             Example 115(a)                                                         116(b) Az-PbCl.sub.2 complex according to                                                                   23.8% of Pb                                            Example 116(a)                                                         ______________________________________                                         "Az" in each case represents "azulmic acid                               

When silver salt complexes, gold salt complexes or platinum saltcomplexes of azulmic acid were used, products stabilised withformaldehyde and with a metal content of over 29 percent by weight couldbe prepared.

EXAMPLE 119

A mixture of 100 g of azulmic acid which was almost free from structuraldefects, 17 g of copper nitrate trihydrate, 300 g of formic acid and 80g of water was stirred at 60°-70° C. for 6 hours, whilst passing 25liters of air through per hour. Thereafter, the solid product wasfiltered off, washed and dried. An azulmic acid-copper nitrate complexwith a content of F₁ structural defects of about 8.9 percent by weightand a content of F₂ structural defects of about 2.3 percent by weightwas obtained. 0.8 percent by weight of oxamide which was formed frommonomeric hydrocyanic acid which had been split off in the course of theoxidative production of structural defects and simultaneous complexingwas also isolated.

The product could be stabilised by reaction with formaldehyde.

EXAMPLE 120

(a) A mixture of 108 g of the azulmic acid prepared according to Example13(a), 1 mol of iron(II) sulphate and 800 ml of distilled water wasstirred at 100° C. for 10 hours. Thereafter, the solid product wasfiltered off, washed with 5% strength aqueous ammonia solution anddried. An iron complex of azulmic acid was obtained which contained arelatively high proportion of structural defects (up to 20 percent byweight) and had the composition: 30.3% C; 3.6% H; 28.7% N; 26.8% O;11.5% Fe

120 g of azulmic acid-iron complex, which contained a high proportion ofstructural defects, prepared according to (a), were treated with 120 gof 30% strength formaldehyde solution in an aqueous medium at 50° C. for5 hours. An azulmic acid-iron complex stabilised by condensation withformaldehyde was obtained, from which no hydrogen cyanide was split offeven at 180° C.

The azulmic acid-metal salt complexes listed in Table 12 which followswere also prepared by the method indicated in Example 120(a).

                  TABLE 12                                                        ______________________________________                                        Example Metal compound                                                        No.     used          Composition of the product                              ______________________________________                                        121(a)  CuSO.sub.4    24.5% C; 2.2% H; 22.6% N;                                                     23.8% O; 3.3% S; 23.9% Cu                               122(a)  FeCl.sub.3    35.7% C; 3.1% H; 33.3% N;                                                     22.3% O; 1.7% Cl; 4.4% Fe                               123(a)  ZnCl.sub.2    23.5% C; 2.2% H; 21.6% N;                                                     19.1% O; 34.1% Zn                                       124(a)  CoCl.sub.2    28.4% C; 2.7% H; 27.8% N;                                                     20.4% O; 20.2% Co                                       125(a)  Cu(OCOCH.sub.3).sub.2                                                                       22.3% C; 2.6% H; 22.6% N;                                                     18.4% O; 33.9% Cu                                       126(a)  SnCl.sub.2    14.7% C; 2.3% H; 12.9% N;                                                     24.8% N; 44.3% Sn                                       127(a)  MnSO.sub.4    28.4% C; 3.1% H; 26.6% N;                                                     24.2% O; 17.6% Mn                                       128(a)  SnCl.sub.2 (0.4 mol)                                                                        23.4% C; 2.7% H; 21.0% N;                                                     21.9% O; Sn                                             129(a)  ZnCl.sub.2 (0.5 mol)                                                                        29.2% C; 2.6% H; 29.5% N;                                                     19.1% O; 19.8% Zn;                                      130(a)  PbCl.sub.2    58.3% Pb                                                131(a)  Bi(NO.sub.3).sub.3                                                                          59.1% Bi                                                132(a)  Tl.sub.2 SO.sub.4                                                                           57.9% Tl                                                133(a)  TiCl.sub.4 (Xylol)                                                                          25.2% Ti                                                134(a)  Zr(SO.sub.4).sub.2                                                                          38.9% Zr                                                135(a)  H.sub.2 WO.sub.4                                                                            55.8% W                                                 136(a)  NiCl.sub.2    29.2% Ni                                                137(a)  AgNO.sub.3    43.1% Ag                                                138(a)  HgCl.sub.2    58.3% Hg                                                139(a)  HAuCl.sub.4   56% Au                                                  140(a)  H.sub.2 PtCl.sub.6                                                                          55.5% Pt                                                ______________________________________                                    

The azulmic acid-metal salt complexes listed in Table 12 were reactedwith formaldehyde by the method indicated in Example 120(b). The azulmicacid-metal salt complex condensation products listed in Table 13 whichfollows were thereby obtained.

                  TABLE 13                                                        ______________________________________                                        Example                                                                       No.       Formaldehyde condensation product of:                               ______________________________________                                        121(b)    Az-Cu complex according to Example 121(a)                           122(b)    Az-Fe complex according to Example 122(a)                           123(b)    Az-Zn complex according to Example 123(a)                           124(b)    Az-Co complex according to Example 124(a)                           125(b)    Az-Cu complex according to Example 125(a)                           126(b)    Az-Sn complex according to Example 126(a)                           127(b)    Az-Mn complex according to Example 127(a)                           128(b)    Az-Sn complex according to Example 128(a)                           129(b)    Az-Zn complex according to Example 129(a)                           130(b)    Az-Pb complex according to Example 130(a)                           131(b)    Az-Bi complex according to Example 131(a)                           132(b)    Az-Tl complex according to Example 132(a)                           133(b)    Az-Ti complex according to Example 133(a)                           134(b)    Az-Zr complex according to Example 134(a)                           135(b)    Az-W complex according to Example 135(a)                            136(b)    Az-Ni complex according to Example 136(a)                           137(b)    Az-Ag complex according to Example 137(a)                           138(b)    Az-Hg complex according to Example 138(a)                           139(b)    Az-Au complex according to Example 139(a)                           140(b)    Az-Pt complex according to Example 140(a)                           ______________________________________                                         "Az" in each case represents "azulmic acid                               

No hydrogen cyanide was split off from the products listed in Examples121(b)-140(b), even at 180° C.

EXAMPLE 141

(a) A mixture of 100 g of azulmic acid which was almost free fromstructural defects, 100 g of gelatin, 100 g of cellulose powder, 0.8 molof phosphoric acid and 1,200 ml of water was stirred at 60° C. for 2hours. Thereafter, the solid product was filtered off, washed and dried.A mixed product consisting of azulmic acid and of cellulose powder andgelatin and their degradation products, which contained a relativelyhigh proportion of structural defects and contained phosphoric acid, wasisolated.

(b) 120 g of the product prepared according to (a) were treated with 1mol of formaldehyde in 300 g of water at 50° C. for 5 hours. Thereafter,the solid product was filtered off, washed and dried. A mixed productconsisting of azulmic acid, cellulose powder and gelatine and thedegradation products of these naturally occurring substances, which isstabilised by condensation with formaldehyde and contains phosphoricacid, is isolated.

EXAMPLE 142

A mixture of 108 g of azulmic acid with a content of F₁ structuraldefects of about 2.5% by weight, a content of F₂ structural defects ofabout 0.5% by weight and a total concentration of amino groups of about19% by weight (=1.12 NH₂ equivalents per 100 g of azulmic acid), 0.2equivalents of formaldehyde (=6 g in 20 parts by weight of water) and500 g of distilled water was stirred at 100° C. for 4 hours. The processproduct was filtered off, washed with water and then stirred with 300 gof a 0.2% strength aqueous ammonia solution at room temperature for onehour, traces of formaldehyde still contained in the mixture beingconverted into water-soluble hexamethylenetetramine. The product(azulmic acid partially condensed with formaldehyde), which had beenisolated by filtration and washed again with water, was then stirredwell with 140 g of microbially active garden mould (moisture content 40%by weight) in 500 g of water at 35° C. for 30 hours, whilst passingabout 50 ml of air over per minute. On working up the mixture, anammonia-containing mixed product consisting of partially stabilisedazulmic acid and microbially active garden mould was obtained. Nohydrogen cyanide could be detected in the filtrate of the reactionproduct.

A total of 5.56 g of ammonia was evolved whilst stirring the partiallystabilised azulmic acid with microbially active garden mould for 30hours. The carbon dioxide content of 90 liters of air, determined in aparallel experiment, and the amount of carbon dioxide produced by themicrobial activity of the 140 g of garden mould (sum=2.5 g of carbondioxide) were subtracted from this amount. It was thus calculated that3.06 g (0.07 mol) of carbon dioxide were formed by decarboxylation of F₁structural defects, that is to say newly produced F₁ structural defectsin the azulmic acid. About 2 percent by weight of F₂ structural defectshad accordingly been formed, per 100 g of partially stabilised azulmicacid employed, in the course of the stirring in the presence of themicrobially active garden mould. The ammonia produced during the primaryformation of F₁ structural defects had remained in the process product.

EXAMPLE 143

(a) 108 g of the stabilised azulmic acid, prepared according to Example4, which was completely free of formaldehyde were dispersed in 1,000 gof deionised water, 103 g (0.3 mol) of cane sugar, 31 g of dried yeast(=standardised purchasable dried yeast preparation from Messrs. Dr. A.Oetker, Bielefeld), 1 g of ammonium carbonate and 1 g of primarypotassium phosphate were added and the mixture was stirred at 35° C.,whereupon the alcoholic fermentation proceeding according to theequation which follows started immediately. ##STR63##

A stream of nitrogen was passed through the apparatus at a rate of 50 mlper minute in order to remove the carbon dioxide thereby formed. The gasmixture issuing from the apparatus was freed from the carbon dioxide itcontained, in a receiver charged with 1 normal aqueous sodium hydroxidesolution. The amount of carbon dioxide bonded by the sodium hydroxidesolution in the form of sodium carbonate was determined tritrimetricallyby the barium carbonate method after 1, 2, 4 and 8 hours. The resultshere were always reproducible and showed that, in contrast to a controlexperiment (yeast preparation, water, cane sugar), the alcoholfermentation process proceeded with only minimum retardation.

After an experiment time of 8 hours, the amount of carbon dioxideevolved was 47 g. This corresponded to a conversion of cane sugar of 94%of theory.

(b) If the fermentation experiment described under (a) was carried outusing the azulmic acid prepared according to Example 1, which had notbeen stabilised, a cane sugar conversion of 18-20% was measured afterstirring for eight hours. Accordingly, the yeast enzymes were soseverely deactivated by the cyanide ions contained in the reactionmixture that the alcoholic fermentation was drastically inhibited.

The test described under (a) thus makes qualitative detection of cyanideions possible.

EXAMPLE 144

A mixture of 108 g (2 base mols) of the black, nonstabilised azulmicacid prepared according to Example 1, 500 g of distilled water and 20 gof a 30% strength aqueous formalin solution (=0.2 mol of formaldehyde)was stirred at 100° C. for 4 hours. Thereafter, the solid product wasfiltered off, washed and dried.

Yield: 112 g of an azulmic acid condensation product which wasrelatively resistant towards the splitting off of hydrogen cyanide. Inthe air space of vessels which were half-filled with the processproducts, a hydrogen cyanide concentration of 0 ppm was measured after astorage at 50° C. for ten days.

The carbon dioxide formed by the production of F₂ structural defectsduring the four hour condensation reaction was determinedtitrimetrically. A total of 0.88 g (0.02 mol) of carbon dioxide wasevolved, which corresponded to a content of F₂ structural defects of0.53 percent by weight.

In a parallel experiment carried out under exactly the same conditions,the mother liquor remaining after filtering off the process product wasconcentrated. The hexamethylenetetramine, which was formed by reactionof the ammonia formed, during the production of F₁ structural defects,with formaldehyde was isolated from the yellowish-brown residue therebyobtained, by extraction with chloroform.

Yield: 2.8 g of hexamethylenetetramine.

Since 140 g of hexamethylenetetramine contained 68 g of ammonia in thebonded form, it was calculated from the yield of hexamethylenetetraminegiven that about 0.08 mol of ammonia were formed in the course of thecondensation reaction. Furthermore, the difference between the molaramounts of ammonia and carbon dioxide showed that 0.06 mol of F₁structural defects had not been converted into F₂ structural defects.The content of F₁ structural defects in the process product wasaccordingly about 4 percent by weight. Total amount of structuraldefects (F₁ and F₂): 4.53 percent by weight.

From this, it follows that, during the condensation reaction, structuraldefects had simultaneously been produced.

EXAMPLE 145

(a) The following substances were stirred into 1,800 g of distilledwater: 108 g of the modified azulmic acid prepared according to Example13(a), 10 g of normal peat, 5 g of a commercially available limed peat,5 g of potassium nitrate, 10 g of calcium cyanamide, 5 g of calciumnitrate, 20 g of a calcium sulphite waste liquor, which contained about40% of lignin-sulphonates and lignin-carbohydrate compounds, 15 g ofcalcium dihydrogen phosphate, 5 g of peat which had been prepared byprocessing peat with waste products of animal and vegetable origin, 10 gof Leuna saltpetre (ammonium sulphate 2 ammonium nitrate), 5 g ofcalcium ammonium nitrate (ammonium nitrate+calcium carbonate), 5 g of alimed peat fertiliser which consisted of carbonated lime, magnesiumcarbonate and about 20% by weight of peat, 5 g of a 10% strengthsolution, rendered alkaline with potassium hydroxide, of humic acids, 50g of a sparingly soluble condensation product of 1 mol of urea and 1 molof isobutyraldehyde, 30 g of a polymethyleneurea of the formula##STR64## in which X=4-12

and 0.5 g of iron(II) sulphate, 0.2 g of copper sulphate, 0.2 g ofmanganese(II) sulphate and 0.1 g of zinc sulphate. The well-stirreddispersion was heated to 80° C. and kept at this temperature for 4hours.

(b) In a parallel experiment, 100 g of the modified azulmic acidprepared according to Example 13(a) were treated with the trace elementsalts listed, in the amounts indicated and under the conditions givenunder (a), but without further additives. From the ammonia/carbondioxide balance thereby determined, it was found that about 0.2 mol ofammonia and about 0.05 mol of carbon dioxide were evolved. This gave amolar NH₃ /CO₂ quotient of 4. The difference between the molar amountsof ammonia and carbon dioxide (0.2-0.05=0.15) shows that 0.15 equivalentof F₁ structural defects and about 0.05 equivalent of F₂ structuraldefects had been produced. About 10.2% by weight of F₁ structuraldefects and about 1.45% by weight of F₂ structural defects hadaccordingly been formed. Total content of structural defects (F₁ +F₂):11.65% by weight.

On the basis of the results of this comparison experiment, it could beassumed that an analogous concentration of structural defects waspresent in the process product prepared according to (a).

(c) After the production of structural defects as described under (a),the well-stirred mixture was treated with 300 g of a 30% strengthaqueous formalin solution at 30° C. for 3 hours. Thereafter, the waterand unreacted formaldehyde were removed by concentrating the reactionmixture under 14 mm Hg until it had a slurry-like consistency. Theslurry, which still contained water, was poured into a pan and dried at60° C. in a vacuum drying cabinet. 333 g of a friable, black-brownsubstance were obtained which, in addition to the trace elements iron,copper, manganese and zinc, also contained potassium, nitrogen andphosphorus as well as about 15 percent by weight of water. The nutrientions were present in the product in a form available to plants.

In the air space of vessels which were half-filled with the processproducts, a hydrogen cyanide concentration of 0 ppm was measured afterheating to 50° C. for 50 hours.

What is claimed is:
 1. A method of supplying plants with nutrients whichcomprises applying to the plants or a plant habitat a compositioncomprising as active ingredient an effective amount of a substance whichis an azulmic acid stabilized by condensation with a carbonyl compoundor an acid addition salt of such a stabilized azulmic acid or a complexcompound of such a stabilized azulmic acid.
 2. The method of claim 1, inwhich said substance is applied to an area of plant cultivation in anamount of about 0.1 to 200 kg/hectare.
 3. The method of claim 1, inwhich said substance is an azulmic acid stabilized with a carbonylcompound selected from the group consisting of aldehydes, ketones andketo esters with reactive carbonyl groups.
 4. The method of claim 1, inwhich said acid addition salt of said stabilized azulmic acid is an acidaddition salt of an acid selected from the group consisting of halideacids, phosphoric acid, phosphorous acid, phospholine oxide-phosphonicacids, dialkylphosphoric acids, polyphosphoric acids, nitric acid, acidsderived from sulfur and organic acids.
 5. A method of improving soilcomprising applying to the soil a composition comprising an azulmic acidstabilized by condensation with a carbonyl compound.